Battery-powered electric trains

Siemens battery-electric train

Trains are about to go electric.

Battery-electric, that is. While electrical propulsion has been the preferred way to move trains for most of a century, the idea of moving them longer distances via battery is one that’s just now being realized.

Like long-range electric cars, it’s a reality afforded by the energy density and longevity of modern lithium-ion battery packs.

In Germany, where only about 40 percent of track is electrified, the trains will clean the air along routes that might have been impractical or prohibitively expensive to electrify, the state of Baden-Württemberg has ordered 20 two-car trains built in Germany by Siemens, who will oversee energy consumption and energy costs over a nearly 30-year service period.

It’s the first such order for battery-electric trains for Siemens Mobility, who will deliver them by June 2023. In them, a lithium-ion battery pack is mounted under the train’s floor and is charged while it moves along via overhead lines, using them to both power the train and charge the battery. When the train reaches a stretch of rail with no overhead lines, the battery takes over.

The new trains are part of Siemens’ Mireo train platform for regional and commuter rail—boasting weight reductions and improved aerodynamics. Configurations range from two to seven cars, and top speed, depending on the version, ranges from 87 to 124 mph [140 to 200 kph].

Germany and France are two markets that have started investing in battery-electric trains. Last month another company, Alstom, announced that it has a first contract to supply battery-electric regional trains for Germany’s Leipzig-Chemnitz line with three-car trains that can cover up to 75 miles and reach a top speed of 99 mph.

That same company has tested hydrogen fuel-cell power as the alternate source instead of batteries. And the Canadian company Bombardier in 2018 launched the Talent 3, an electro-hybrid train that can cover up to 62 miles on non-electrified track, with a modular approach to configuring motors and batteries.

[From Green Car Reports.  Here are two related articles: First Order for Mireo Plus B Battery, and Alstom signs first contract for battery-electric trains ]

Unfortunately, none of the articles says how long it takes to charge the batteries, or, put it another way, how many k's the train must travel using the electric catenary for each k of travel under battery power. 

‘UK-first’ battery train outperforms diesel

From Electrek

A “UK-first” intercity battery trial train proved that single battery technology can outperform diesel engines cost-effectively.

Hitachi Rail, Angel Trains, and TransPennine Express just wrapped up the trial, which took place in the north of England. It proved that powerful batteries offer significant benefits for emissions, fuel savings, and air quality.

Hitachi has already rolled out passenger battery trains in Japan and Europe, like the Masaccio hybrid in Italy. The intercity battery trial train in the UK demonstrated that the 700 kW battery could push the train past 75 mph and power it for over 70 km. The battery matches the weight of a diesel engine and is installed in the same undercarriage space, ensuring no risk of track degradation and no impact on the passenger environment.

The battery trial train delivered better-than-expected results in fuel savings, cutting fuel costs by 35-50%. One key way it achieved this was with an “Eco-mode” where the battery fully powered sections of the route, showing that the technology is more than ready for real-world use.

This success gives Hitachi the green light to move on to a full intercity battery-electric train, with an estimated range of 100-150 km. That would allow significant stretches of non-electrified routes to go battery-powered, avoiding the need for expensive infrastructure like overhead wires in tunnels or stations.

I put this article here because it's interesting, and suggests ways forward to cut emissions from land transport, which, including cars and light trucks, contributes roughly 20% to total greenhouse gas emissions (CO2 and nitrous oxides).  But it's not very clear, and further research didn't help.  For example, the writer talks about a 700 kW battery.  Did they mean 700 kWh, which is the measure of stored power (for example, a typical EV has 50–70 kWh of stored electricity) or what they said, 700 kW, which is a measure of output at any moment?  Also, the article gives the impression that the train was run completely on battery, than says, "“Eco-mode” where the battery fully powered sections of the route".  Does this mean that some parts of the route were not fully powered by the battery, but also used diesel?  Is this new train a hybrid?

Never mind.  The sharp drop in fuel costs (35-50%) shows that not only is the battery technology environmentally better, but it will also save money.  I've talked about bi-mode trains, which are diesel-electric when there is no overhead wire (or third rail) but switch to electric when there is an alternate power source.  Adding batteries to the mix would make these trains even more flexible, and allow them to be integrated into the train network more effectively.  I've also discussed battery-powered trains, here, and here.   I'm also going to be doing a piece on NSW's new bi-mode diesel/electric trains.  Keep an eye out for it.

I can't help thinking that a carbon tax would concentrate minds wonderfully, and we'd see much more rapid progress with battery and bi-mode trains if we had one.

Battery-powered vs fuel-cell trains

From Treehugger.

Just about everyone agrees that the best way to power a train is with electricity from overhead wires; the only problem is that it is really expensive to install. Even in Europe, which is pretty dense and has a great rail system, as much as 40% of the 25,000 miles (40,000 kilometers) of track is not electrified, and on many of these lines, the demand isn't high enough to ever justify the cost, which can be huge. There isn't only the wiring, but often all the bridges have to be rebuilt higher to handle the height of the catenary wires and pantographs on the roofs of the trains.

European governments want to get rid of diesel-powered trains as part of the fight against global heating, so they have been buying hydrogen-electric multiple units (HEMU), which are electric trains powered by fuel cells running on hydrogen.

But there is another player in the game: battery electric multiple units (BEMU) – trains powered directly from giant batteries, which are getting better and cheaper by the day. They are now pushing 75 miles (120 kilometers) in range; Rail Journal quotes Brahim Soua of Alstom, who says “This was not the case several years ago where the level of autonomy was close to 40km. This is thanks to an improvement in the battery’s capability to store more energy for the same mass of battery.” This is good enough range to skip through many non-electrified sections of Europe.

Now Oliver Cuenca of International Railway Journal reports that the battery-powered trains cost 35% less to buy and operate than hydrogen trains. The batteries don't have to be replaced as often as fuel cells, either, so maintenance costs will be lower. Cuenca notes some caveats:

However, the study assumes that only ‘green’ hydrogen made by electrolysis using electricity from renewable sources will be used. In reality, the cheaper so-called ‘grey hydrogen,’ made as a by-product of the chemical and oil industry, will be used in some cases.

The problem is, there is no point in replacing the diesel trains if they run on gray hydrogen, which is made from natural gas and emits 9.3 kg of CO2 for every kg of H2 in the process. The hydrogen-hype people say this is just an intermediate step, that "The plan is that hydrogen will be produced on site via electrolysis and wind energy at a later stage of the project." But as we noted before, "while Germany's renewable electricity supply has grown dramatically, they still get half their power from coal and are closing their nuclear reactors. It will be a very long time before they are making hydrogen from electrolysis."

Unless it was made at night...

"The study also assumes that hydrogen will be more expensive than electricity because electricity is needed to produce the hydrogen in the first place. This may not be true, as electricity used to produce hydrogen generated at night will likely be significantly cheaper due to much lower demand compared with the daytime electricity used when most electric regional trains operate."

Except that if the trains operate during the daytime, they can be charged at night with the same cheap electricity, just like people do with their electric cars. [Well, not quite: most ppl travel less than 100 km per day, while a battery electrc train could do 10-20 tmes that, so will have to charge during the day as well as overnight]And it will store a lot more of that electricity. Hydrogen is a lousy battery; the efficiency of splitting it from the oxygen is now up to about 80%. Then there are losses compressing and cooling it, and then the fuel cell is only about 50% efficient, giving an overall efficiency at the wheels of about 35%. This all might get better with improved technology, but batteries are running at 80% efficiency now[Musk has said that Tesla's batteries were 90% efficient] and they are getting better too. As energy expert Paul Martin notes,

"A technology which uses 3x as much energy as its competitor, at bare minimum, will have a hard time competing—if they share the same energy source. So if H2 is going to be competitive, beware— it won't be "green" hydrogen they reach for. It'll be the only kind you can currently buy—BLACK hydrogen made from fossils without carbon capture. And that's a highly questionable way to "green" a diesel."

See also :Battery-powered electric trains

GWR's battery-electric train--the verdict

 I talked about this before.  This new video gives more useful detail.

• GWR has been investigating battery-electric trains to replace diesel on branch lines.
• Straight-out electrification is expensive.  The overhead wires and the catenary posts are costly.  On high-volume routes, this cost is worth it. But on less-used lines it is not.
• On this route, the diesel train produces 960 kg of carbon dioxide vs 235 kg per day for the battery units (a 75% reduction)  With renewable energy sources for the electricity, this could be reduced to 26 kg/day (a 97% reduction)
• The charging rail is on the ground, but is only activated when the train is over it (much safer!)
• It reaches full charge in 4 minutes (for 5 miles of travel).  The charger is connected to a bank of batteries (on the ground) which is connected to the national grid.  This stops the massive drain of power from tripping the local grid.
• So, unlike an overhead-wire electrification, it's just one charging station, which means there is no need for catenary posts and adjacent electrical infrastructure.  It's all off-the-shelf equipment, and can be installed with ease, even while services are running.
• Even with current battery technology, the batteries only need to be swapped out once in the unit's operating life, and can then be recycled.
• It's been tested under all sorts of conditions: rain, ice, leaves on the line, snow and baking heat, with full heating on, and it's worked without problems.
• It's far more efficient than diesels in terms of power usage, with 79% efficiency, with an electricity consumption of 2.4 kW per carriage per mile, and is obviously much quieter than a diesel.
• Diesels are more expensive on fuel and maintenance, but were cheapest on infrastructure. Overhead electrification was most expensive on infrastructure, but on a par with battery-trains on other costs.  Costs per train-mile:  £5/ train-mile, diesels £4/train-mile, battery-trains £2.52/train-mile.
• The batteries have a possible range of at least 80 miles (130 km).  [Though, by my calculations, that would take an hour to charge].  It is possible, though less efficient, to charge the batteries via the overhead cable, i.e., this battery-electric train could run along mixed electrified and unelectrified track.

Land transport contributes +-20% to CO2 emissions, and more to NOx, which are much more potent greenhouse gases.  Cars and light trucks make up most of this, but diesel for rail is not insignificant.  And it's horribly polluting.   

See also my articles on battery-electric trains.

Slashing the cost of electric cars

There is a ferment of new battery technologies being researched and developed.  Whether this one will work commercially, we don't yet know.  But it isn't the only progress with battery technologies out there. 

If it does work, it will cut the cost of storage 20-fold, making renewables with storage barely more expensive than renewables without, and therefore way cheaper than coal and gas, and also slashing the cost of EVs.  Normally, these things take two or three years to start large-scale commercial production, so we won't see any imminent price collapse.  Meanwhile, though, li-ion batteries are falling by 20% a year in cost, which means they're halving every 3 years.

From TheLead:

A new battery technology that could significantly reduce the price of electric cars and home battery systems has taken a major step towards commercialisation.  South Australian researchers from the University of Adelaide have secured an A$1 million research contract with a Chinese battery manufacturer to develop the new technology and bring it to market within 12 months.

The patented design uses non-toxic zinc and manganese, two metals that are abundant in Australia, and incombustible aqueous electrolyte to produce a battery with a high-energy density. The researchers estimate the cost of this new electrolytic Zn–Mn battery to be less than US$ 10 per kWh compared with US$ 300 per kWh for current Li-ion batteries[actually, closer to $200-$250], US$ 72 per kWh for Ni–Fe batteries and US$ 48 per kWh for Lead–acid batteries.

The battery is designed by Dr Dongliang Chao and Professor Shi-Zhang Qiao from the University of Adelaide’s School of Chemical Engineering and Advanced Materials. The high-energy, safe battery opens up markets where the battery weight, size and safety are essential factors, including automotive and aerospace, and domestic and commercial buildings, and grid-scale energy storage.

Dr Chao said although there were other Zn-Mn batteries on the market such as the dry cell, they were not rechargeable or recyclable and did not present high-energy density due to a different chemical reaction mechanism. “I can imagine this battery being used on all vehicle types from small scooters to even diesel electric trains. Also in homes that need batteries to store solar power, or even large solar/wind farms,” he said.

“With more sustainable energy being produced – such as through wind and solar farms – storing this energy in batteries in a safe, non-expensive and environmentally sound way is becoming more urgent but current battery materials – including lithium, lead and cadmium – are expensive, hazardous and toxic.

“Our new electrolytic battery technology uses the non-toxic zinc and manganese and incombustible aqueous electrolyte to produce a battery with a high energy density.”

Dr Chao and Professor Qiao began working on the project in South Australia about 12 months ago and patented the technology at the beginning of this year.  Chinese battery manufacturer Zhuoyue Power New Energy Ltd, whose current batteries are lead-based, has committed $1 million to develop the new technology.

The ongoing research work and initial product development will be conducted in Adelaide with manufacturing expected to take place in Australia and China.

Dr Chao said the project would combine the new electrolytic battery technology and the company’s battery assembling technology.  “In addition, the battery uses basic materials and simple manufacturing processes so will be much cheaper to produce and easier to recycle than existing batteries of comparable energy density,” Dr Chao said.

The ZED70 Australian Electric ute (pickup truck, bakkie)

NSW's bi-mode diesel/electric trains

 I've talked before about bi-mode trains.  Most 'diesel' trains are actually diesel-electric.  A diesel generator charges batteries (in the old days, lead-acid batteries, and for all I know, that may still be the case) which then drive the electric motors which turn the wheels.  Why such an apparently complicated arrangement?  It's because electric motors have a higher torque than diesel motors, and can therefore accelerate away from stations more quickly.  A bi-mode train is one that can, when it's possible, directly use electricity from an overhead wire or third rail to drive the engines, obviating the need for diesel; or can use the diesel engine when there is no electricity source.

There is also a battery-electric train, which is not quite the same thing.  This charges up its batteries whenever there is external electricity, then uses the stored power in its batteries when the wire ends.  This option, won't work, however, in places where the distance between population centres is large, such as Australia, because batteries are not yet energy-dense enough to cover long distances.  

Electric traction is the "best" for trains in terms of operating cost.  But the capital and maintenance costs are high, and so expanding electrification to the routes where there are only a few trains a day is not cost-effective.

In NSW, which is between California and Texas is size, the rail network within a couple of hundred kilometres around Sydney is electrified, but the majority (in terms of track, not population) of the state is served by diesel.  The NSW State government has started replacing aging diesel trains with bi-mode trains, which can switch between diesel(-electric) in the countryside to electric in the city.  Despite a minority of the network being electrified, the reduction in emissions is still significant. 

In the UK, Hitachi isn't just building battery-electric trains, it's also developed bi-mode trains, as this video below shows.

For long routes, bi-mode traction makes sense.  For shorter non-electrified routes, battery-electric makes sense.  It shows you that we can cut rail emissions, if only we put our minds to it.

Locos which keep going when the wire ends

I was doing some research on "bi-mode" or "dual-mode" locomotives, which can use both electric power from an overhead catenary, as well as diesel power.   Diesel-electric locos already use electric engines to turn the wheels: the diesel engine drives an electric generator which in turn drives the wheels.  Why this apparently inefficient arrangement?  Because an electric engine can provide full torque at zero RPM, unlike plain diesel engines, allowing for faster acceleration from stops.  

Locos which can use both diesel and electricity as energy sources are called electro-diesel locos, whereas, locos using a diesel motor to drive an electric generator are called diesel-electric.  Some diesel-electric locos also have a battery to allow for a larger power draw during acceleration.  

Obviously, if the loco is on a stretch of track where there is electric power, then it would make sense to use the electricity available to run the loco's electric engine.  That is exactly what Siemens Vectron Dual-Mode locomotives does.

From Siemens website:

 

Vectron Dual Mode – keeps going where the wire ends

The Vectron Dual Mode is the up-to-date answer to changing route requirements. The dual power locomotives unite the advantages of full-featured diesel locomotives with those of electric locomotives. This combination empowers you to respond flexibly at all times to your traction requirements – so you'll always keep moving, with or without an overhead wire.

Whenever an overhead wire is available, it should be used. Electrical operation is much more cost-effective and environmentally friendly than diesel operation. But because Germany [and the UK, Australia, the USA .....] will continue to have many non-electrified sections of track for a long time to come, many diesel locomotives still run under an overhead wire – without actually using it. This makes very little economic or ecological sense. The Vectron Dual Mode excels in both operating modes, offering a real alternative to diesel-only operation.

Whether you want to react flexibly to unplanned diversions or boost environmental performance in conurbations: the Vectron Dual Mode offers you a wealth of advantages in your day-to-day operations.

With the Vectron Dual Mode, you'll handle a wide range of traction tasks much more economically than with a standard diesel locomotive. Every kilometre saves fuel, and thereby reduces energy costs. You'll also reduce the number of hours your diesel alternator set is operating. Altogether, you'll benefit from a reduction in energy and maintenance costs of up to 53%.  [The savings obviously depend on what percentage of the total network is electrified.  On the other hand, diesel locos have to keep running even when they are stationary.  Given that hybrid cars use up to 40% less fuel than petrol cars because the engines don't run when the car is stationary, and also because they recharge their battery as they slow down or go down a hill, significant energy savings appear quite possible, provided the loco also has a battery.]

The issue of environmental pollution is becoming increasingly important in cities and metropolitan areas. With the Vectron Dual Mode, you'll make an important contribution to sustainable freight transport. By taking advantage of electricity wherever possible, you reduce carbon dioxide, nitrogen oxides and particulate matter emissions. This lets you reduce your annual local emissions by 950t of CO2, 6t of nitrogen oxides and 37kg of particulate matter compared with a standard diesel locomotive – and significantly improve your fleet's environmental performance.  [Again, the percentage of electrified track will alter these numbers.  For example, only 10% of Australia's railway track is electrified.  However, a much larger percentage of track in urban areas and conurbations is electrified, and a larger percentage of total traffic takes place on these networks.  For example, in Victoria, V-Line trains which serve regional and country destinations travel for part of their journey on electrified tracks.  On my journeys from a provincial town 200 kms from the city into the big smoke, half the distance is electrified.]

There is another advantage.  To extend existing electrified sections, installing overhead electric wires has to be done from the edge of the existing electrification to the next station or to a depot, which makes for substantial lump-sum outlays.  In other words, it has to be done in expensive chunks.  With a bi-mode loco, electrification can proceed at, say, 5 kilometres at a time, so that the electrified network can be gradually extended over time.  The loco just keeps going under diesel power when it reaches the end of the wire.  Also, the electrified sectors don't need to be contiguous, as the diesel engine could be used across the gaps.  

A good idea.

See also:

• Battery-powered electric trains
• Battery-powered vs fuel-cell trains

Plunging battery costs

Storage is key to our transition to a carbon-free economy.  Even if we have a grid with a good mixture of wind and solar, there will still be periods when the two together don't provide enough electricity and other periods when they provide too much.  And though we can provide electricity to trains or trams via an overhead cable or an additional rail, we can't do that for cars or lorries.  For them, we will need stored energy.  Now, that's provided by petrol or diesel, but in future it will have to come from electricity stored in batteries.  So it's really important that batteries get cheap.

The chart below comes from BNEF via Climate Denial Crock of the Week.

Source

The cost of storing 1 kWh has fallen from  $1000 in 2010 to just over $200 in 2017, an 80% decline, which works out to a cumulative/compound annual rate of decline of 20%.  The rate of decline of the last 3 years, though, has been much faster.  From 2014 to 2017, the rate of decline has been 29% per annum.  This faster rate of decline has coincided with the development of Tesla's first battery gigafactory in Nevada.  Right now, Tesla needs all the batteries it can produce for the ramp up in Model 3 production. So it's unlikely Tesla will be cutting the price of its batteries for public sale yet.  But in 6 months' time, as the gigafactory itself moves towards completion, and Model 3 production beds down, I have no doubt Tesla will be cutting the prices of its Powerwall and Powerpack products. 

Let's be conservative and project a continued rate of decline in battery prices of 20% per annum, though it's far more likely that with 12 battery gigafactories opening round the world, prices will decline faster than that.  At 20% per annum continued rate of decline, by end 2020, the cost per kWh will be down to $100/kWh of storage, half what it is now.

Currently the cost of the Powerpack, Tesla's utility-scale storage solution, is $387/kWh, but that includes the inverter/transformer.  Inverter costs are also falling, so it seems entirely plausible that by the end of 2020, Powerpack costs will have been at least halved.  Currently, the cost of power from the Powerpack is 10.5 cents/kWh delivered ($387/365 days/10 years).  A 50% price cut will take it down to 5 cents/kWh delivered, or $50/MWh.  Currently, gas peaking costs more than $150/MWh.  So it's probable that by 2020, no new gas baseload plants will be built.  Instead, utilities will start using battery storage to firm and balance electricity output.  Also, the cost of wind/solar with 10 hours of storage will be $70 or below, comparable to gas baseload in the US (where gas is cheap), and cheaper than gas baseload in the rest of the world.  Just as coal demand has peaked, so will gas demand peak not long after 2020.

The fall in battery costs will also drive down the sticker prices of EVs to the same as ICEVs.  $100/kWh for storage is where this will happen, but battery costs won't stop falling when they've reached $100/kWh.  They will halve again, making EVs and grid/household battery storage irresistibly cheap.

This is only 3 years away, the end of 2020.  In 3 years' time, EVs will be as cheap as ICEVs, and sales will be exploding.  In 3 years' time, renewables with storage will be even cheaper than they are now relative to coal, and starting to compete head-to-head with gas.  Frankly, those corporations and countries (legacy car manufacturers, oil companies, Saudi Arabia/Kuwait, utilities, etc.) which do not start to plan now for the deluge of profound change that is coming will be wiped out.  The good news for everybody else is that carbon emissions will start to fall really fast in the 2020s, giving us a fighting chance that emissions will be close to zero by 2050, which is what we have to achieve to limit global warming to 2 degrees C.

Weaning ourselves off fossil fuels

A 5 year moving average of the global temperature anomaly.  Source: NOAA 

Only a few dotty denialists continue to (or pretend to) doubt that global warming is real, it's happening, and we are responsible.

Fossil fuels are very convenient.  They are excellent stores of energy, conveniently transportable, and not variable like renewable energy sources (though fossil fuel power stations do have a nasty habit of breaking down in hot weather--Australia has experienced 6 major coal power stations tripping over the last few weeks).  But they produce CO2, which might be invisible and only a small part of our atmosphere, but traps outgoing infra-red radiation, causing the world to heat up.  And that process appears to be accelerating.  Fossil fuels also produce plenty of visible pollution, and burning fossil fuels leads to the deaths of 6 million a year around the world.  In the past, we put up with fossil fuels because they were cheaper than the alternative.

However, now fossil fuels have a second disadvantage, one which increases every year.  They are more expensive than renewables.  This is how coal dies — super cheap renewables plus battery storage shows how the costs of new wind farms with battery storage in Colorado are below the costs of running old coal power stations:

Solar, wind, and battery prices are dropping so fast that, in Colorado, building new renewable power plus battery storage is now cheaper than running old coal plants. This increasingly renders existing coal plants obsolete.

Two weeks ago, Xcel Energy quietly reported dozens of shockingly low bids it had received for building new solar and wind farms, many with battery storage (see table below).

The median bid price in 2017 for wind plus battery storage was $21 per megawatt-hour, which is 2.1 cents per kilowatt-hour. As Carbon Tracker noted, this “appears to be lower than the operating cost of all coal plants currently in Colorado.”

The median bid price for solar plus battery storage was $36/MWh (3.6 cents/kwh), which may be lower than about three-fourths of operating coal capacity. 

In India, nearly two-thirds of existing coal power generation is no longer price competitive with new solar and wind projects.  In fact replacing high-cost coal power stations would save Indians US$8 billion per year.

Over the last couple of years, in many countries new wind and solar farm have got cheaper than new coal power stations.  Now, renewables are becoming cheaper than existing coal power stations, even though existing coal power stations are cheap to run because they have been fully depreciated.  In other words, building brand new wind and solar farms would actually be cheaper than continuing to run older coal power stations, cheaper even after interest is paid and depreciation costs deducted.  Why would we continue to dig up, transport and burn coal, with all its attendant filth and impacts on a climate which is already heating too fast, when we can save money by building out wind and solar farms?

The answer, from increasingly desperate denialists and coal and oil interests is that renewables are too variable.  We need, they say, the stability of fossil fuels.  No we don't.  

This article from PV Magazine, Seasonal patterns show a need for more solar in the U.S. electricity mix, discusses the seasonal mix of wind and solar in the USA.  Solar is (obviously) stronger in summer, and wind complements this by being stronger in other seasons.  There isn't just a seasonal complementarity: wind in the mid-west "wind corridor" is stronger at night, when the sun doesn't shine, and dies down during the day when it does.  Using both wind and solar produces a much more stable total output than using either individually.  The PV Magazine article also talks about geographical differences in generation and demand:

For all of this to provide benefits on a wider geographical basis it will be necessary to have the infrastructure and market design to rapidly move and trade electricity across regions. The Federal Energy Regulatory Commission is tracking more than 4,600 miles of new transmission projects that it gives a high probability of being completed over the next two years. This is nearly 20-times the length completed in the first 11 months of 2017.

So, a mixture of wind and solar combined with long-distance power lines to bring power from windy or sunny regions to places where the demand is.  

But storage will still be needed, which might come from two sources.  The first is concentrated solar power (CSP):  

An hour away from Area 51 in the Nevada desert, a beacon shines inexhaustibly day after day. And while its proximity to the famous classified zone makes some travelers believe they have seen something alien, the artifact is far from being extraterrestrial.

The beacon is part of a revolutionary solar generating and storage technology that may finally make solar power an undeniable competitor to coal and nuclear. With the first utility-scale facility already operating in Crescent Dunes, Nevada (and several more under development around the world), we are hopefully seeing the beginning of a new era in energy production.

The technology is called concentrated solar power (CSP) and uses a system of mirrors to concentrate solar energy and turn it into thermal by heating up a medium. The Crescent Dunes Power Plant, developed by the company SolarReserve, uses salts to capture and store the energy from the sun. The result is solar power available 24 hours a day, that can meet utility demands just like a conventional fossil fuels, except without any emissions or hazardous waste. 

[Read more here--it has a nice explanation of CSP]

CSP has fallen in cost by 2/3rds over the last 4 years, from 15 cents to less than 5 cents per kWh ($150/MWh down to $50/MWh)  It's still more expensive than wind and solar, but they can't provide power 24/7 like CSP can.  To smooth out a blended output from wind and solar (PV) farms, CSP will be very useful.

And of course, there are batteries.  The "Big Battery" in South Australia has already proved itself again and again over the last six weeks since it was opened, by helping to stabilise the grid when coal power stations repeatedly tripped.  But it's not big enough to provide substantial time shifting, not yet.  Battery costs will halve over the next 3 years, and probably halve again over the subsequent 3 too.  At that point, batteries will become ubiquitous, both behind the meter and at wind and solar farms and on the grid.  

The intrinsic variability of renewables is manageable.  Using different sources of green electricity--wind, solar PV, and CSP--from geographically separated weather zones connected by HVDC lines, and stabilising the grid with batteries will reduce overall variability of supply, and at a lower cost than continuing to use fossil fuels*.  

Converting electricity generation to renewables is key.  If we can do that, almost all other industrial processes can be electrified using green electricity.  For example, we can switch land transport (cars and lorries and trains) to run off batteries.  We can convert all heating to electricity.  Even where it seems impossible, for example in air transport, we can in principle produce methane from CO2 and hydrogen using green electricity via the Sabatier process, or we can produce a whole range of hydrocarbons via the Fischer-Tropf process from seawater.  It's energy inefficient but it doesn't matter if green energy is cheap enough--and it's getting cheaper every year.

Even 5 years ago, wind and solar were more expensive than coal and gas.  Now they're as cheap as or cheaper than fossil fuels, and their costs will go on falling.  Electric cars are within a couple of years of matching the buying cost of petrol/diesel cars.  Green electricity and green transport are or soon will be cheaper than fossil fuels.  Weaning ourselves off fossil fuels will prove surprisingly easy. 

* We might keep existing gas peaking power plants going for emergencies, but instead of using natural gas (methane) to run them, we could instead use synthetic natural gas produced by the Sabatier process produced with green electricity.

Just stop burning fossil fuels!

 Honestly, it's quite simple. We have to stop burning fossil fuels to stop global temperatures rising.

Simple in concept, but not in execution.  We have to replace a couple of thousand coal power stations with wind, solar, and nuclear power.   And we have to transition our whole car and light truck fleet to EVs.  1.6 billion of them!   And find ways to power air travel with renewable fuels.  Electric planes aren't quite there yet.  Oh, and then there's cement and steel, where the manufacturing processes emit CO2, quite apart from the energy used.   But, essentially, if we can halve emissions, we will also halve the decade-by-decade rise in global temperatures from +-0.2 degrees to +-0.1 degrees.  Which will give us more time to reduce emissions from those harder sectors.

Together, land transport and electricity generation contribute roughly 50% of emissions, globally.  And the good news is that in these sectors, the clean energy alternatives are cheaper than fossil fuels.

For example, in Australia, BYD now sells an electric car (EV) which costs the same as a Toyota Corolla. Since EVs are 4 times as efficient as petrol cars (most of the fuel burnt in a conventional petrol engine is wasted as heat, and isn't used to drive the car forward) they are already much cheaper to run than petrol cars. Now, they're cheaper to buy as well. What's more, when the regulations are promulgated (why so slow, Federal Government?) you will be able to run your house on the electricity in your car. The BYD will have roughly 45 kWh of stored electricity in its battery. Average daily household use in Australia is 15 kWh. So you'll be able to charge your EV when power is cheap (midday, and again after 10 pm) and use it when power is expensive (4 pm to 9 pm). So for the same price as a petrol car, you'll get a giant household battery, cheaper car fuel bills, and much-reduced electricity bills.

This has been made possible by the collapse in battery costs. And that deep, and continuing, plunge has been parallelled by the fall in solar panel costs. While high latitudes will never be able to run on solar alone, in low and mid-latitudes, such as Australia, we will be able to run our grid on 100% solar electricity, combining it with 6 or 8 hours of storage. And EVs will be part of that revolution, as every household and every business gets them.

All these trends are being driven by market forces. Extremely competitive Chinese manufacturers are driving down prices. BYD spends as much on research as its total profit. CATL, the world's largest battery manufacturer, has introduced a sodium-ion battery. Sodium is a lot cheaper than lithium, and is also much safer. The same vigorous competition is driving down solar panel costs.

That's not to say we're out of the woods. There are powerful regressive forces which want to delay the transition, and useful idiots yelling loudly about how unfair it all is. Bring back steam trains!

Plus there are methane emissions from cattle and sheep, and CO2 from cement and steel. Methane is 80 times as potent a greenhouse gas, over a 10 year horizon (after which it decays into CO2) There's air transport, and sea transport, and home heating (bring on heat pumps!).

However, we must move faster.  The seas are dying, and half the tree of life is going extinct.  We should attempt to halve emissions by 2035, and halve them again by 2045.  With costs of solar and batteries plunging, that's achievable.

GWR's New Battery Powered Train

Step by step we move away from fossil fuels in railways. 

 Electrification is overall cheaper on busy lines. To date, diesel has been cheaper on less-used lines, because the higher capital cost of installing third-rail/overhead-wire technology isn't offset by the cheaper running coats of electricity.    

I've talked before about battery-powered electric trains which charge from the overhead catenary when they travel on track with electrification, allowing them to travel some way on un-electrified track. 

 Which of these alternative approaches would be better would depend on distances travelled and how fast overhead catenary-charged batteries can charge.  In Australia, for example, rural towns are much further apart than the towns served by this line in England, which are roughly 5 miles apart.   This would require more batteries, on the train and next to the track, and more charging time.  

An alternative is a locomotive which can run on either diesel or electric power, called "electro-diesel" or "bi-mode"  locos (not to be confused with diesel-electric motors), such as the new trains in NSW (which I know I wrote about here on Volewica, but have been unable to find the article)

Things are getting very ugly

 

Source: Off Target, from the UN Environment Programme
Note:  I believe that the UN is using the convention that methane is 20 times as potent a greenhouse gas as carbon dioxide over 100 years.  The better way to count methane, I think, is its effect over 20 years, when it is 80 times as potent a green house gas as CO2.  This would significantly increase the percentage of emissions from agriculture above the ~20% shown in this table.

Next year, this humungous El Niño could drive temperatures to 1.7 or 1.8 degrees C above pre-industrial levels.  This is, of course, catastrophic.  Things will get very ugly, unless we redouble our efforts to slash emissions.  

What can we do?

First, what can governments do?

✔️ Set a renewable energy target.  The percentage of renewables+nuclear in electricity generation needs to rise by 6-8% a year, or more, if we are to eliminate electricity's emissions before it is too late.

Emissions from electricity generation are just under 30% of total global emissions.  We may not yet be able to go above 90 or 95% renewables in the grid, because we don't have long-term storage to offset periods of dunkelflaute, but we can certainly aim for 90%, and reconsider what we need to do next when we get there. 

How would this work?  Each utility would be required to reach the levels set in the RET each year.  Those which exceeded this target would get credits, those which didn't would have to buy credits, either from their more successful peers, or from the government.   This would encourage utilities to replace coal and gas with wind/solar/batteries/nuclear/hydro. I include nuclear, but in truth, it can't be built fast enough.  But if there is already nuclear available, it shouldn't be closed down. 

If we aim for a maximum of 10% fossil fuels in electricity generation within 10 years, we will have cut emissions by 27%.  And, remember, in principle, every use of energy can be electrified.  So removing fossil fuels from electricity generation is key.

✔️ Every country should introduce a carbon tax.  It doesn't have to be swingeing to start out with, but it should rise every year, and the pathway should be clear to everybody.  To prevent emission leakage — you tax your industries while others don't tax theirs — you must also tax imports from countries which do not have an R.E.T. or a price on carbon.  (See my posts on a carbon border tax)

✔️ We need to accelerate the replacement of petrol/diesel vehicles (ICEVs) with EVs.  15% of emissions come from transport.  Because even when we reach 100% of sales being EVs, it will take 10-20 years for all ICEVs on the roads to be replaced.  This is too long.  Most countries are nowhere near 100% EV sales, even though this percentage has risen sharply over the last 9 months.   To accelerate this process, we could, for example, ban the import of new and second-hand ICEVs, or slap 100% taxes on them.  By taxing new petrol cars and subsidising EVs, we would drive a wedge between the up-front costs of EVs and ICEVs.  Ethiopia has already done this.  This policy should apply to two and three-wheeled vehicles, too.  Countries which do this deserve reduced carbon border taxes.  And we should press on with bi-mode and battery trains and electric planes.

✔️ We need to replace oil- or gas-based household and industrial heating with heat pumps.  They're four times as efficient as gas, oil, or electric heaters, and so are cheaper to run, but they have higher up-front costs.  They will require government subsidy to start the revolution rolling.  

All of these combined will cut emissions by 50 or more.  If we also switch to low-emission steel and cement, the emissions cuts could reach 65%.

Second, what can you do?

✔️ The steps above will leave mostly agricultural emissions to be reduced, which (but see note on graphic above) are ~20% of emissions. This is too hard for governments to act on — now.   People love their meat too much to give it up.  But it won't go away.  When we've cut emissions by 70%, agriculture will dominate what's left over.  And action will no longer be postponable.  

✔️ Until then, you personally can cut beef, mutton, pork and cow's milk out of your diet, which would more than halve your emissions from the food you eat.  Even better: if land is freed from animal raising, it can be re-wilded, which reduces the level of Co2 in the atmosphere.  Negative emissions!  If you really care about global heating, this is something direct you can do.  You can only force governments to switch to renewables by acting collectively (by voting), and though we shouldn't give up trying to get collective action, we don't need anybody else's permission to eat less meat.  It's something you can start today.

The position is far from hopeless.  We have the technology to slash emissions from electricity generation and transport. What we lack is the will to act.  Perhaps the upcoming Godzilla El Niño will shift the political logjam.  Make it so.

The EV1 and Tesla

 In the early days of the automobile, electric drive trains were almost as popular as petrol ones.  The problem was that the batteries then were lead-acid, which are not nearly as energy dense as lithium-ion batteries.

Comparing the two chemistries side-by-side, lithium ion achieves an energy density of 125-600+ Wh/L versus 50-90 Wh/L for lead acid batteries. In other words, if you were to drive the same distance using each type of batteries in an identical vehicle, the lead acid battery could take up to 10 times the volume that the lithium ion would, and it’s also heavier. (Source)

So GM's EV1 was an experiment.   It was powered by lead-acid batteries, and its range was limited to 60-80 miles (100- 130 km).  This video from the BBC gives a brief history of its development, with optimistic videos from the early 1990s.

 

GM stopped selling the EV1 in 1999, and cancelled all the leases after 2002.  Sales had been limited, and the company did not think battery technology was advancing fast enough to justify the extension of the program.  The whole story is complicated; read the Wikipedia article about it.  There were many within GM who opposed its development and extension, and there were many dealerships who were hostile, because EV1 had so few mechanical parts compared to petrol cars.

As Wikipedia says: 

The EV1's discontinuation remains controversial, with electric car enthusiasts, environmental interest groups and former EV1 lessees accusing GM of self-sabotaging its electric car program to avoid potential losses in spare parts sales (sales forced by government regulations), while also blaming the oil industry for conspiring to keep electric cars off the road.  

Critics of GM and proponents of electric vehicles claim that GM feared the emergence of electrical vehicle technology because the cars might cut into their profitable spare parts market, as electric cars have far fewer moving parts than combustion vehicles. Critics further charged that when CARB, in response to the EV1, mandated that electric vehicles make up a certain percentage of all automakers' sales, GM came to fear that the EV1 might encourage unwanted regulation in other states. GM, which was also joined by other automakers, battled against CARB regulations, going as far as to sue CARB in federal court.

Was it a dismal failure?  No.  A noble one.  Because it led the CARB (California Air Resources Board) to mandate electric cars, and this in turn led to Toyota developing the first hybrid, the Prius, in 1997.   Also GM's withdrawal of the EV1 and the rather vindictive crushing of all models, led to the founding of Tesla.  Musk tweeted in 2017:

Few people know that we started Tesla when GM forcibly recalled all electric cars from customers in 2003 & then crushed them in a junkyard.  [This] was done against the will of their owners, who held a candlelight vigil all night to protest the death of their cars. Since big car companies were killing their EV programs, the only chance was to create an EV company, even tho it was almost certain to fail.

Although Musk was extremely influential in its development, Tesla was actually started by two engineers in Silicon Valley who wanted to prove that electric cars could be successful after GM cancelled the EV1 program:

Elon Musk may be the CEO of Tesla but he didn’t actually start the company. Tesla was founded in 2003 by two Silicon Valley engineers, Martin Eberhard and Marc Tarpenning. They wanted to prove that electric cars could be better than gasoline-powered cars. Although Tesla Motors was incorporated on July 1st of 2003, the seeds of the company go back to 1990 when both founders met.

Eberhard’s passion for cars was kindled after he went through a divorce and wanted to buy a sports car but he couldn’t buy a car that only got 18 miles to the gallon. The arguments for global warming were becoming undeniable.

This decision fueled his interest to begin research on high performance electric vehicles which didn’t quite exist at the time. Eberhard went through every power source you can think of. Eberhard soon discovered that electric cars were the most efficient. Further research led him to an electric car hobbyist community where he met AC Propulsion – a boutique electric car maker. What was even more interesting was the fact that the company had a superfast electric sports car called TZero. The TZero proved to Eberhard that an electric car didn’t have to be slow, he invested in the company with the hopes of obtaining a copy of the car. Eberhard even thought of joining forces with the company to build a production level electric car rather than a hobbyist vehicle.

Sadly he soon discovered that his ambitions were not in sync with the culture of the firm. At this point Eberhard considered launching his own company. By 2003 Tarpenning and Eberhard knew that they wanted to start an electric car company, starting with a two-seater sports car with an induction motor and lithium ion batteries. Eberhard wanted to give credit to the man who patented the AC induction motor, Nikola Tesla. Tesla was a 19th century inventor and his work led to the discovery of alternating current which is a primary way of transmitting electricity today.

On July 1st 2003, the company was incorporated and by August they moved into the company’s first office building in Menlo Park, California. By fall of 2003, Eberhard and Tarpenning started refining their idea in a bid to make formal pitches to investors. The first round of funding came from family, friends and a handful of venture capitalists. The investments were small because there was no one to lead the round.

Earlier in 2001 Tarpenning had dragged his friend Eberhard to see PayPal co-founder Elon Musk to speak at a Mars Society conference at Stanford. They introduced themselves and didn’t reach out until late March 2004. Elon was interested in the idea and in April 2004 the paperwork of their partnership was finalized.

Musk went on to lead a $7.5 million round in 2004 and became the chairman of the board. In 2006 the company unveiled the prototype of its Tesla Roadster which entered production in 2008. The Roadster Tesla brought something entirely new to the car industry, the electric car was produced with specs that could meet consumer needs. The first model could travel 250 miles on a single battery, its acceleration and speed were also at par with other consumer level sports cars.The story of Tesla is still being written but it all started with the curiosity of two engineers – Martin Eberhard and Marc Tarpenning.  (Source)

Here's a fascinating video about the founding of  Tesla:

 

As they say, the rest is history.  

I wonder just how much GM  regrets cancelling the EV1.  There wouldn't be a Tesla if they hadn't--there wouldn't be an electric car industry without Tesla, as the second video makes clear--and now Tesla's a formidable competitor, and Musk is a multi-billionaire.  

GWR's battery train goes into service

 I've talked about these trains before, here and here, but they were previously still in test mode.  Now, passenger services have started.  GWR is testing them on this short stretch of track under real operating conditions, and if they work here, they will be rolled out to other branch lines where the traction is currently diesel.  The discussion of the battery chemistry is interesting. 

This way of reducing CO2 and diesel emissions from rail is one that could be copied by other countries, including those with bigger distances between towns, like Australia and Canada.    

Oil companies know hydrogen is a dead end

 From CleanTechnica

Reasonable minds may differ on the question of whether hydrogen fuel cells have a place in the clean-energy future. However, it’s a fact that the fossil fuel giants have been heavily hyping hydrogen, and it’s not hard to see why, as the vast majority of hydrogen is currently produced from natural gas.

Oil companies (which now want to be known as “energy companies”) are keen to be seen as green these days. Shell, BP, and Total are investing large sums in EV infrastructure, at all levels of the charging value chain. They also present their hydrogen business as a tool to reduce carbon emissions. However, recent comments by an oil industry lobbyist concerning the industry’s efforts to undermine climate regulations indicate that Big Oil’s double-dealing strategy — butterflies and grandchildren for the press, lobbyists and campaign cash for policymakers — hasn’t changed.

Michael Liebreich, the founder of BloombergNEF (originally named New Energy Financing before it was purchased by Bloomberg), presents some new thoughts about the issue in a recent interview published in Recharge.

Liebreich (who is no tree-hugging liberal, but a pro-business supporter of the UK Conservative Party, and an advisor to Norwegian oil giant Equinor) isn’t against hydrogen per se, but he believes (as do many in the clean energy field) that it makes sense only in certain use cases.

“In an attempt to guide governments and industry players away from the [oil industry-sponsored] spin, Liebreich has created what he calls his Hydrogen Ladder, a simple chart showing which use cases for H2 are uncompetitive, which are unavoidable for decarbonization, and which sit somewhere in the middle,” writes Recharge’s Leigh Collins.

Green represents areas where H2 is essential, red where it's pointless, i.e.,
 where alternatives are cheaper and more efficient.  Source: @MLiebreich

At the top of Liebreich’s ladder lie applications such as ammonia-based fertilizer and oil refining, which currently use highly polluting grey hydrogen produced from fossil fuels, and are responsible for 3–4% of all global carbon emissions. In the middle are use cases in which hydrogen might make sense, such as seasonal power storage, steel, chemicals, shipping and long-haul aviation. At the bottom “uncompetitive” end of the ladder are light-duty vehicles and domestic heating, applications in which hydrogen fuel cells clearly make no sense (battery-electric vehicles and heat pumps are far more efficient, and already well established in the market).

In Liebreich’s view, the logical course would be to replace polluting grey[/blue] hydrogen with green hydrogen produced by electrolysis in the applications at the hydrogen-friendly top of the ladder, and to cease futile attempts to make hydrogen work for cars and other applications at the bottom of the ladder.

However, that’s not the approach that the oil companies are taking. They’re pouring money and lobbying efforts into convincing politicians to direct public investment to building a “hydrogen economy,” with considerable success, notable in Canada, Germany, and the UK.

This is not because oil company execs are ignorant of the science — you can bet they’re as well informed as you and I, if not more so. Liebreich believes that leaders of fossil fuel firms know that hydrogen is a poor choice for cars and home heating, but are pushing it as a solution in order to slow the pace of electrification.

“If you’re an oil and gas company, in a way, talking about hydrogen is kind of a two-way bet because if it works, then you’re embedded in the hydrogen industry — but if it doesn’t work, you’ve delayed the transition to the thing you don’t make, which is electricity,” he tells Recharge. “So why wouldn’t you promote hydrogen for inappropriate use? For the things that are not at the top of the ladder, that are fairly down — local trains, local buses, cars, delivery vehicles — why not promote it? Because at worst it creates confusion, which is great [for them]. And these companies have an interest in this [electric] stuff not moving too fast, I’m afraid — for all their good words.”

The Noemi amphibious electric seaplane

I've talked about Sweden's Heart Aerospace ES-30, a four-engined electric plane capable of carrying 30 passengers for up to 200 kilometres on battery power and 800 km with hybrid assist.

Elfly's Noemi (for "no emissions") aircraft is a two-engined amphibious seaplane which can carry 9–13 passengers and up to one tonne of cargo for 200 km from city harbour to city harbour, or even, since it is amphibious, from airport to airport, needing only short distances for take-off and landing.  As they say:

City center to island? Easy. Harbor to airport? Not a problem. Sightseeing tours through fjords, natural parks, or cities with strict emission and sound regulations? By design.

With no need for bulky infrastructure, capable of taking advantage of naturally plentiful waterfronts and ubiquitous electricity, we can offer commuting, sightseeing, and cargo solutions that bolster local businesses and ecological resilience alike.

No need to commute to some faraway airport - and back again. Forget the stress of traditional flying and simply board a quiet, smooth flight right from your city harbor.

Born in Norway: A land with more than a thousand fjords and half a million lakes. With most of our population straddling a line between high mountains and the sea, it is difficult, expensive, and environmentally challenging to build adequate infrastructure. Our Noemi seaplane is an effective, non-intrusive solution born from our way of life, capable of reducing hours we’d spend in cars or trains to mere minutes in the air.

Source: Elfly

There are lots of new electric plane start-ups.  Some of them will fail, no doubt.  But this ferment of activity is very encouraging.  Technological advances happen when there is pressure to innovate, and we are clearly seeing that in the electric plane domain.  And as energy density of batteries increases, the range and payload will also increase.   Trans-oceanic flights?  Not yet.  But 200 km plus range will allow you to cross continents by hopping from airport to airport – just as they used to when the range of petrol aircraft was no better than the range of electric planes today.  With zero emissions.

So ... the good news about global warming

Global temperatures continue to rise.  Which is terrifying.  But also very depressing, because we appear to be helpless, individually, in stopping global warming.   So what is the good news? Is there any?

Some broad background.    Electricity generation is only part of total global carbon emissions (25%) but it is key, because in principle you can electrify almost the whole economy: transport (+-20%) can be electrified via electric cars, buses and trains, heating can be electrified, and most energy uses in industry can too.  (And we can create synthetic natural gas via the Sabatier process) That leaves agriculture forestry and other land use (AFOLU -- 25%) but that in turn includes 15% from burning forests, which can easily be stopped.  These remaining sectors will be hard: iron and steel 7%, air transport 2%, cement 5%.  To make iron you need to reduce iron ore (basically iron oxide) to iron by heating it with coal or charcoal, producing carbon dioxide as a by-product.  Batteries are still too heavy for aircraft, though we can use bio-kerosene.  And cement is created by heating calcium carbonate and driving off the carbon dioxide.  So let's say 75% of current carbon emissions can be stopped by electrifying the economy and producing electricity via renewables.

Source

China (30% of global emissions) is very rapidly moving towards renewables in electricity generation.

Source

The IEEFA forecasts that China will add 22 gigawatts of wind, 16 GW of hydro, 6 GW of nuclear, and 16 GW of solar this year (2016):

With electricity demand expected to grow by up to 3 percent year-on-year in 2016, this 62 gigawatts of additional zero-carbon electricity capacity will be more than sufficient to meet total electricity demand growth, which is why coal consumption is forecast to fall again this year. China Shenhua said its total 2016 coal sales volumes could decline more than 8 percent year-on-year.

At the same time China is setting new global renewable energy records, rapid improvements in energy efficiency are combining with an ongoing structural change in the nature of Chinese economic growth (2015 GDP growth was up 6.9 percent). The economy is decoupling from growth of electricity demand (of 0.5 percent year-on-year). Tertiary industry accounted for 50.7 percent of economic activity, exceeding 50 percent (up from 48.1 percent in 2014) for the first time.

There’s nothing to indicate this electricity-sector transformation won’t continue.

China’s State Grid Corp. Chairman Liu Zhenya (head of the world’s largest power provider) says his company rejects the so-called all-of-the-above energy strategy—which encompasses fossil fuels—to meet China’s evolving power needs and address climate change. Liu argues that it is better to move on to the next generation of energy technologies and that China believes it might as well start now. He concluded that the only hurdle to overcome is the mindset: “There’s no technical challenge at all.”

(Source)

The US (15% of world emissions) is moving steadily towards 100% renewable energy.  In Q1, 98.5% of new generating capacity was renewable.  Only 1.5% was gas.  This is prolly an exceptional quarter in the shorter term, but the trend is clear.  In 2015, 69% of new electricity US generation capacity was from renewables.

Source

Of course, generating capacity is often quite different from the amount of power generated, since fossil fuel plants generally are used for considerably higher percentage of the time (their “capacity factor”). That’s why renewables now make up 18 percent of total U.S. installed generating capacity — but only about 14 percent of our total power production.

On the other hand, FERC doesn’t track rooftop solar, so its estimate of solar capacity added is certainly low. Indeed, FERC’s data sources only “include plants with nameplate capacity of 1 MW or greater,” so it’s hard to know how much small-scale renewable power generation they may have missed.

It is increasingly clear that we don’t need to add significant amounts of any new grid capacity that isn’t renewable for the foreseeable future. In part that’s because demand for utility power generation has been flat for almost a decade — and should continue plateauing for quite some time — thanks to rapidly growing energy efficiency measures (and, to a much lesser extent, thanks to recent increases in rooftop solar).

We also know that renewable power — both new wind and solar — is now winning bids for new generation around the world without subsidies. Some bids are coming in at under four cents per kilowatt hour!

Studies from NOAA and others — and real-world examples around the globe, such as Germany — show that the U.S. can absorb vastly greater percentages of renewables than we currently have, just with existing technology. Yet NOAA’s research shows that, with nothing more than an improved national transmission system, “a transition to a reliable, low-carbon, electrical generation and transmission system can be accomplished with commercially available technology and within 15 years.”

A 2015 study showed that we could “decarbonize the electricity supply with a proportionally small requirement for BES [Bulk multi-hour Electricity Storage] because gas provides much of the intermittency management even when the carbon emissions intensity is cut to less than 30% of today’s U.S. average.”

Thus, we really have more than enough natural gas plants in most places to take us to the point where electric vehicles, second-life EV batteries, advanced solar thermal power and other affordable bulk storage would be needed to finish the decarbonization of the grid post-2030.

So we may well see many more quarters in the years ahead like the last one.

(Source)

India (7 % of global emissions):  

Meantime on the Indian solar front, January saw yet another breakthrough as solar tariffs dropped to a new low of  4.34 rupees/kWh [6.5 US cents/kWh]. This builds on the 20 percent decline achieved in 2015 (and the 80 percent decline in just five years).

The latest detail: Fortum Finnsurya Energy of Finland winning a reverse tender auction to build a 70-megawatt solar plant under National Thermal Power Corporation’s Bhadla Solar Park tender. The remaining 350 megawatts put up for auction were won at bids of 4.35 rupees (140 megawatts by Rising Sun Energy and 140 megawatts by Solaire Direct) and 4.36 rupees per kWh (70 megawatts by a newer entrant, Yarrow Infrastructure), indicating that the 4.34 rupee bid was not an outlier. It marks a 7 percent decline from the previous record-low solar bid established in November.

In that bid, SunEdison won 500 megawatts at 4.63 rupees per kilowatt-hour. This was repeated in a 350-megawatt solar auction by SoftBank in December. The total installed cost of solar in India dropped by more than 20 percent in 2015 alone.

A big piece of India’s transformation in occurring through grid-efficiency reforms, exemplified in January by Piyush Goyal, India’s energy minister, announcing an $11 billion investment to roll out 30 million solar irrigation pumps for farmers over the next three to four years. Annual savings on existing farm subsidies is modeled at $3 billion, suggesting the program is entirely and immediately commercially viable.

(source)

[Meanwhile in Dubai, solar has plunged to US3 cents/ kWh.  Why is India still more expensive than Dubai?  Partly the monsoon which brings rain to India for 3 months of the year (July to September) which reduces insolation in India even though India is closer to the equator than Dubai; partly the cost of capital which is significant for solar because all the expenses are up front.]

Europe (10% of emissions).  Europe was an early mover on renewables.  Already 40-50% of electricity in some countries (Denmark, Portugal) or regions (the former East Germany) is produced by renewables (non-hydro).  And several European countries are planning to ban all petrol-/diesel-engined car sales as early as 2020. 

So countries emitting 62% of the world's CO2 are switching their electricity generation into renewables.  But it's not just the largest emitters who are moving towards renewables.  Lots of countries with smaller CO2 footprints are also moving towards green generation.  Just three examples: Mexico (solar), Chile (wind + solar + CSP), South Africa (solar + CSP)  Then there a few who aren't doing much (Russia, Australia, Poland).

This almost global switch is being driven by government policy, but also by the collapse in renewables prices.  There is a virtuous circle, called a learning or experience curve.  As we use more of a new technology, its price falls, which leads us to use more, which leads to further price falls, etc, etc.  So, solar is falling by 15% to 20% per annum, which means it's falling by +-60% over 5 years.  Wind is falling by 10% per annum. Lithium-ion batteries by 15% or more per annum.  The battery in your laptop cost $2500 15 years ago, $250 4 years ago and now you can buy one on line for AU$ 50 - 100 or US$35 - 70. 

According to Ray Kurzweil [1] [2] [3], who has been much more right than wrong in his forecasts over the last 20 years, solar will dominate world energy within 16 years.  His point is simple: solar has been doubling installed capacity every 2 years for 20 years.  Like computer chips. there is no sign we've reached the end of that road.  Solar now produces 1% of total global energy.  In 2 years time that will be 2%.  In 4, 4%.  In 6, 8%.  In 8, 16%.  In 10 32%; in 12 64%.  Game over.  To quote the first article I referenced above:

Just like computer processing speed—which doubles every 18 months in accordance with Moore's law—the nanotechnology that drives innovations in solar power progresses exponentially, he says.

During his latest Big Think interview, Kurweil explained:

"Solar panels are coming down dramatically in cost per watt. And as a result of that, the total amount of solar energy is growing, not linearly, but exponentially. It’s doubling every 2 years and has been for 20 years. And again, it’s a very smooth curve. There’s all these arguments, subsidies and political battles and companies going bankrupt, they’re raising billions of dollars, but behind all that chaos is this very smooth progression."

So how far away is solar from meeting 100% of the world's energy needs? Eight doublings, says Kurzweil, which will take just 16 years. And supply is not an issue either, he adds: "After we double eight more times and we’re meeting all of the world’s energy needs through solar, we’ll be using 1 part in 10,000 of the sunlight that falls on the earth. And we could put efficient solar farms on a few percent of the unused deserts of the world and meet all of our energy needs."

Needless to say, the implications of cheap solar power would be truly staggering, revolutionizing virtually every aspect of life and geopolitics. Potentially dangerous nuclear power would become obsolete; dirty energy sources like coal and oil would be a thing of the past; and the world would no longer have to kowtow to corrupt governments that just happen to be resource-rich. 

So many other global issues—like impending water and food crises—would also no longer be issues if a cheap, renewable energy source existed. "We’re awash with water, but most of it's salinated or dirty," says Kurzweil. We have the technology to desalinate and clean water, but it is very costly. Cheap solar would change that. If we had inexpensive energy, scientists could also grow hydroponic fruits and vegetables, supplying the growing demand for food and "recycling all the nutrients and materials so there's no ecological impact at all." They could even "grow meat without animals by cloning muscle tissue," eliminating the need for disastrous factory farming, he says.

(Source)

Sounds utopian, doesn't it?  Yet who would have said  even 10 years ago that we would all these days be carrying advanced computers in our pockets?  And it will prolly not happen as he forecasts, because concentrated solar power is in there with a chance, and wind will still have a role to play because it diversifies solar (wind and solar are not just uncorrelated: they appear to have a small negative correlation--the wind blows more when the sun isn't shining)   But essentially the point remains.  In 20 years time, all electricity globally will be generated by renewable sources.  Note that last year, for the first time, developing countries invested more in renewables than developed countries. (Remember that the data show nominal investment in renewables, i.e., before price falls.  In real, volume, terms, investment will have risen not 5% but 25%.)  Developing countries are not doing it because they are concerned about global warming.  If renewables were too expensive they would make excuses--after all they're poor, and most of the CO2 already emitted was from currently developed countries.  They're doing it because renewables are cheap.  

And they're going to get cheaper.  Let's conservatively assume solar falls by 50% over five years.  Electricity from solar will fall in cost to US cents 1.5 to 3 over the next 5 years.  Five years after that it will cost USc 0.75 to 1.5.  And 5 years after that USc 0.4  to  0.8.  This will be irresistibly cheap.

Meanwhile, electric car sales are doubling every 18 months, as the cost of lithium-ion batteries plunges.  Last year they formed just 0.7% of global car sales.  This year it should be over 1%.  Sales are quadrupling every 3 years,  And that's not going to stop, because (a) global warming is obviously happening and it's happening scarily fast, so governments will be pushing electric cars and (b) we're moving down the learning/experience curve, just as we did with the first petrol-driven automobile, the Model-T Ford.

Well, those are the reasons to be optimistic that  mankind will do enough to prevent global temperatures from rising another 1 or 2 C.  Does that mean we must stop worrying, stop fighting?

No.  There are powerful vested interests which would like to slow this revolution.  Demented plutocrats.  Fossil fuel interests.  The usual suspects.  And the Right, at least in America (and Australia), has become actively hostile to rationality, logic and science.  You have only to look at the Republican candidates for the US presidency to see this pattern.  For some bizarre reason the Right opposes this shift to clean cheap energy, a shift which will transform the world and raise living standards everywhere.  And given the risk of runaway positive feedbacks (the melting of methane clathrates in the tundra and on shallow continental shelves, for example), we need to accelerate this transformation.  We need to slash emissions by at least 3% per annum.  And although global emissions may have peaked, they haven't yet started falling.  Until they do, steadily and persistently, we cannot relax.  We still need to remove subsidies from fossil fuels ($450 billion a year, globally, not including the costs of pollution).  We still need to tax carbon emissions if only to remove externalities which favour destructive energy sources to the cost of mankind.

The battle is far from over.