EV prices will keep on falling

 Battery costs continue to fall.  If anything, the rate of decline is accelerating.   

This has huge implications for EVs, obviously.  EVs will very soon have the same "sticker price" as petrol cars (they are already much cheaper to run).  EVs will rapidly rise to 100% of car sales.

But it also is crucial for de-carbonising electricity generation.   

Let's take a simple example.  Within the tropics (between 23 degrees north and south of the equator), we could run the grid entirely on solar.  For example, at Brisbane (latitude 27 S), in mid-winter (June), there are 10 hours and 25 minutes of daylight.  With tracking solar, which faces due east in the morning and due west in the afternoon, the output profile is "square", i.e., rises almost immediately to the maximum and stays there, compared with, say, rooftop solar, where the output rises in a sine wave to its maximum over a couple of hours over midday.  Demand at night is 2/3rds of demand during the day, so we would need something like 8 hours of storage.  If battery costs have halved, that means that 8 hours of storage will now cost what 4 hours used to.  

Outside the tropics, combining wind and solar and 8 hours of storage will be able to replace fossil fuels.  Only in high latitudes (north of 60 degrees), with long winter nights and high demand for heating, will we require seasonal storage (hydro or power-to-gas).  

Remember also, that EVs are storage on wheels, with the average EV having 70 kWh, or 3 plus days (72 hours plus) of average household demand (20 kWh per day).  This will be combined with several hours' worth of storage at every utility-scale solar farm, plus additional storage at substations to stabilise the grid.  

This video from the Electric Viking discusses the plunging costs of battery storage and its implications.

Making hydrogen electrolysers super efficient

The traditional electrolysis process is relatively inefficient.   If you use surplus green electricity to produce hydrogen and then burn the hydrogen to make electricity, its round-trip efficiency is low, much lower than alternative energy storage techniques:

 

Flora noted that converting power to hydrogen and then using the fuel to generate power has a relatively low round-trip efficiency. Round-trip efficiency is the percentage of electricity retrieved after being stored.

The technology to convert power to hydrogen and back to power has a round-trip efficiency of 18%-46%, according to data that Flora presented from the Massachusetts Institute of Technology and scientific journal Nature Energy. In comparison, two mature long-duration technologies, pumped-storage hydropower and compressed air energy storage, boast round-trip efficiencies of 70%-85% and 42%-67%, respectively. Flow batteries, a rechargeable fuel cell technology that is less mature, have a round-trip efficiency of 60%-80%. 

(Source: S&P Global --- Hydrogen technology faces efficiency disadvantage in power storage race
)

[Incidentally, Elon Musk claims that's Tesla's lithium-ion batteries have a round-trip efficiency of 93%]

But an Australian start-up, Hysata, is developing a process which enormously increases the efficiency of electrolysis.    I've already talked about this company and their super efficient hydrogen electrolyser, here.  

This update is from ARENA (Australian Renewable Energy Agency)

A pioneering, all-Australian hydrogen electrolyser technology is getting the chance to prove itself at a commercial scale.

If it works, the project has the potential to transform the economics of renewable hydrogen production.

ARENA’s support has helped develop this new technology since it was a concept in a University of Wollongong laboratory. That work saw a spin-off company, Hysata, established to commercialise the development.

Now, Hysata will receive $20.9 million ARENA funding as part of a $47.5 million project. Hysata will build and test a 5 MW system at its new Port Kembla manufacturing facility.

The plan then is to move the entire system to Rockhampton in Queensland, for installation and trials next to the Stanwell Power Station.

Queensland government-owned power company Stanwell Corporation is providing the site and facilities, and also backing the project with $3 million.

ARENA CEO Darren Miller says the project is a crucial step to enabling purchase orders for the technology.

“Hysata’s electrolyser technology could be a game-changer for renewable hydrogen,” Mr Miller said.

“The demonstration at Stanwell’s site will be key to unlocking commercial demand for Hysata’s product by proving the technology works at scale.

Currently, the production cost of renewable hydrogen (using renewable energy) is at least twice that of hydrogen produced from fossil fuels. Hysata says its technology will slash costs and produce hydrogen “well below” a competitive target price of $2 per kilogram (approx. US$1.50/kg).

FYI, if there’s one number you should remember, it is that price of $2 per kilogram. That’s the key to competing with fossil fuel-derived hydrogen and fully unlocking renewable hydrogen’s industrial and energy future.

It’s all in the bubbles.   All electrolysers work by passing an electric current from electrodes through H2O – water. The current splits the water into its two parts, hydrogen and oxygen. That process takes energy.

Now, if the entire process were 100 per cent efficient, all that energy would go into splitting the water. Nothing else.

But, until now, electrolysers have also produced a lot of heat. That’s because, just like an electric heater at home, they have electrical resistance.

The heat generated is not only wasted energy, but it must also be removed. Electrolysers need a lot of cooling and that uses even more energy.

So, if you can reduce resistance, a greater proportion of energy is available to split the water. Also, the system generates far less far less heat, which in turn requires less cooling.

Hysata has tackled the problem by completely redesigning their electrolyser to remove all the main sources of electrical resistance.

It turns out, that means eliminating hydrogen and oxygen bubbles. When bubbles form on the electrolyser’s electrodes, they reduce the surface area available for electrolysis and increase resistance.

In fact, Hysata says it has completely eliminated bubbles from its system and cut electrical resistance to virtually zero. As a result, Hysata says it expects a fully operational electrolyser will stay cool through good air ventilation alone.

The combined effect is what has raised the overall efficiency of a Hysata electrolyser to around 95 per cent. That’s a huge jump on current technologies, which operate with efficiencies closer to 75 per cent.

To put that in context, to make renewable hydrogen competitive with its fossil-fuel derived alternative, the International Renewable Energy Agency (IRENA) in 2020 set an electrolyser efficiency target of up to 85 per cent … by 2050.

I'm not sure that hydrogen by itself is in fact the future.   To transport it, you need to compress it and refrigerate it, which takes additional energy, further reducing its round-trip efficiency.  Also, it makes gas pipes brittle, and, because its molecules are so small, it easily escapes through the gaps in the molecular lattices of gas pipes or storage tanks.   But if you convert it to methane, using the Sabatier process, it's the equivalent of natural gas, and in fact is called synthetic natural gas (SNG, which is a bit of an oxymoron, no?)  And then you can use the existing gas distribution system and gas storage system, as well as existing gas turbine electricity generators.  On the other hand, to make SNG, you need a source of CO2, and unless you use the escape gases from a gas-turbine power plant flue, you have to produce CO2 using direct air capture, which is still very expensive.

We will need seasonal (or long-term storage)  to reach 100% renewables, and hydrogen, or more probably, SNG, will be how we fill that gap.  So, if this can be commercialised, it will be a huge step forwards towards a 100% green energy system. 

World's biggest offshore wind coy comes to Australia

From RenewEconomy

Ørsted, the world’s biggest offshore wind developer, has confirmed it plans to make major investments in Australia, with the initial focus on the country’s first offshore wind zone in Gippsland, Victoria.

The Danish company’s newly appointed head of Asia Pacific, Per Mejnert Kristensen, says the company has been monitoring developments in Australia for many years, and opportunities in offshore wind, as well as onshore wind, solar and “power to X” (green hydrogen), are getting very interesting.

“We feel that with our experience and track record, we will be able to play a strong role here in the renewable sector,” Kristensen told RenewEconomy in an interview on the weekly Energy Insiders podcast.

Kristensen says Ørsted’s initial focus is on gigawatt scale projects in the Gippsland offshore wind zone in Victoria, which is likely to be officially declared shortly, allowing for the first detailed feasibility studies to be conducted.

The company is also about to open its first permanent Australian office in Melbourne.

“We are talking to a number of different stakeholders and partners here,” Kristensen says. “At this point in time, I’m not able to say anything specifically regarding that. We really feel that now we are kicking off our efforts in Australia.”

Major players converging on Victoria offshore wind

Ørsted, whose interest in Australian offshore wind was first reported by RenewEconomy earlier this year, joins a host of major international energy players jockeying for position in the nascent Australian offshore wind industry.

These include Iberdrola, Shell, Equinor, Macquarie Group’s Corio, Copenhagen Infrastructure Partners, and Vena Energy, plus a host of smaller players such as OceanEx, Flotation Energy, Bluefloat, and more.

There are now more than 20 declared projects representing more than 50GW of proposed capacity. See RenewEconomy’s Offshore Wind Farm Map of Australia

All eyes are on Victoria, which has set a target of 2GW of offshore wind in production by 2032, 4GW by 2035, and 9GW by 2040. Its newly announced 95 per cent renewables target for 2035 counts heavily on offshore wind.

But the federal government has also flagged five initial offshore wind zones, mostly grouped around Victoria and NSW, and also likely to expand to Tasmania, South Australia and Western Australia.

Gippsland is already the focus of at least five competing projects, including the 2.2GW Star of the South project, regarded as the most advanced in the country, and the most recently announced 2GW Blue Marlin project, unveiled by Singapore-based Vena this week.

Joint venture with Copenhagen Infrastructure Partners

Interestingly, Ørsted just this week announced a major joint venture with Copenhagen Infrastructure Partners, the majority owner of the Star of the South project, to develop 5.2GW of offshore wind capacity in Danish waters.

Ørsted already has 13GW of offshore wind capacity under operation, and a stated goal to expand this to 30GW by the end of the decade.

Kristensen says the industry – and consumers – are suffering from rising costs “everywhere in the world”, particularly for steel prices, but also for interest rates.

“It is putting some of both pressure on cost. I think that would be fair to say. And I think that’s acknowledged by everyone. Now, this, of course, cannot cannot keep going like this. So we expect it to be a temporary thing with the extreme levels that we’ve seen in many parts of the world now.

“It is … putting pressure on the companies and the capital, we have to … have a very robust balance sheet. We have strong support from our investors. And we have a very good credit ratings.

“So I think (Ørsted) remains in the strongest position to keep developing our offshore wind ambitions. And we are indeed on track to to achieve this 30 gigawatt into 2030.

“It would be fantastic if we could get the first offshore wind farms going, for example, here in Victoria, just before the turn of 2030.

Ørsted has 30GW offshore wind target for 2030

“We know that this would require the frameworks to be in place rather quickly. But we also have the sense that this is what the Commonwealth Government and the Victorian state government are working very hard on.

“So I would say that, that it will be be tight, but I think it’s still it is possible with the right framework. And indeed, for me personally and for (Ørsted), we would indeed love Australia to be part of this 30 gigawatts.”

Ørsted recently set a 100 per cent renewables target for all its 22,000 suppliers by 2025, and Kristensen says the company is hopefully of sourcing Australian content – where it makes sense – when it does begin projects in coming years.

Ørsted built the world’s first offshore wind farm in 1991 and now lays claims to a 30 per cent share in the global industry.

Power-to-X technology

Kristensen also says the company is interested in onshore wind and solar projects in Australia, as well as the “Power-to-X” technology that is included in its newly announced deal with CIP in Denmark.

Power-to-X describes the production of green hydrogen or green fuels to help power heavy industry and heavy transport. “We are a long term player,” Kristensen said.

Ørsted has been cited as a potential bidder for CWP Renewables, which has a gigawatt scale portfolio of existing and pipeline projects in wind, solar and storage. Ørsted declined to comment on specific opportunities.

The proposed wind farms off Victoria's Gippsland coast will together provide at least 80% of Victoria's electricity, and 20% of the nation's.  Ignoring rooftop and utility scale solar, they will add enough renewable capacity to take the nation's renewable energy output to nearly 60% of the total o ver the next 10 years.

It's dark, it's still, it's dunkelflaute

 From Energy Networks

Whether you’ve heard of it or not, dunkelflaute (dunk-el-flout-eh) is a challenge our energy systems will need to manage. Dunkelflaute is a German word that literally means dark doldrums or dark lull. It describes events where there is minimal or no sunshine and wind for extended periods, usually occurring during winter. Dunkelflaute is a specific problem of low electricity output that occurs in highly-renewable electricity systems. The challenge it presents is obvious – how to guarantee electricity supply when the dark lull descends?

In Australia, this has been referred to as a renewable drought. A recent lull in wind generation in South Australia is a small-scale snapshot of what could become a much larger problem in future.

AEMO data (via Open NEM) shows that across 11 and 12 June, wind power (represented by green in Figure 1 below) generated fewer than 4,800 MWh of a total demanded 55,000 MWh, only 8.7 per cent of total generation. This is compared with 9 and 10 June when wind power generated 46,000 MWh out of a total demanded 73,000 MWh, contributing 63 per cent to generation.

 

Germany is in a similar position as South Australia in terms of renewable penetration. Renewable electricity in Germany contributed 45.4 per cent of electricity consumption in 2020, more than coal, oil and gas combined. Germany also has significant transmission connection with the EU, possessing more interconnectors than any other country in Europe.

In Germany there is a growing fear of dunkelflaute as the share of renewable generation increases and displaces dispatchable generation. The type of event to cause dunkelflaute doesn’t have to be severe weather like we saw in Texas in February. It can be as benign as several still winter days in a row. 

How do we manage dunkelflaute?

A recent Grattan Institute report Go for net zero referenced dunkelflaute as ‘the winter problem’. In the document, Grattan notes that an energy system with 90 per cent renewable electricity would reduce emissions by 105 million tonnes at a cost of less than $20 per tonne. The final 10 per cent, however, is much trickier to achieve because the electricity system must increasingly rely on firming options.

The immediately available electricity storage option that might come to mind is batteries – but batteries tend to be best suited to managing hourly fluctuations across the day, charging from the midday sun and then discharging to help with the evening peak. Today’s batteries are not well placed to manage longer durations, with most having less than four hours of storage. The Victorian 300MW Big Battery project in Geelong is slated to be able to provide electricity to 400,000 households for one hour at full charge. That may be big but managing dunkelflaute will require a much bigger battery.

Broadly, there appear to be three options that could assist the transition from 90 to 100 per cent renewables.

Lots of renewable generation and transmission

The first is building a diverse renewable generation fleet all across the country in hopes that the wind is blowing or sun is shining somewhere, while ensuring sufficient interconnection to transport large quantities of electricity all across the country. This option would result in a large amount of electricity being ‘wasted’, along with lowering the utilisation of interconnection, while still leaving room for dunkelflaute in severe cases.

There is a positive correlation between solar energy across the National Energy Market (NEM) . When the sun is shining in one area, it is also likely to be shining in others, and visa versa. The absence of solar energy in one region may not be easily replaced by solar in another as different regions can be affected by similar weather systems.

Deep storage

The second option is building deep storage, like pumped hydro, that by its nature is well placed to provide storage capacity. Snowy 2.0 for example will be able to provide 2000 MW of generation capacity for 175 hours at full capacity. Grattan has modelled that across a 10-year period, up to 9GW of storage capacity might be required to bridge the largest gap between renewable generation and demand over 14 days. That’s about nine Snowy 2.0’s assuming they all start at full capacity.

This type of deep storage solution is likely to sit idle most of the time and could be challenging to finance, with Grattan rightly noting that many optimal sites for pumped hydro have already been developed. Additional interconnection would also be required to connect this deep storage, which may again be poorly utilised.

Developing this much deep storage is likely to be incredibly costly and unlikely to be in customer’s best interests.

Zero emissions dispatchable energy

The third and most promising option is building zero-emissions dispatchable energy, consisting of renewable gas usage in gas powered generation plants. Natural gas already provides a similar role in today’s generation mix and renewable gas will allow much of the current infrastructure to be utilised to support high levels of variable renewable electricity generation.

Frontier Economics examined the role of gas powered generation in South Australia during renewable droughts to support a highly-renewable system and found that using gas powered generation could reduce the overall system cost by between 28 to 35 per cent per year, depending on the extent of the renewable drought during winter.

Figure 3 – Indexed systems cost for 2030 and 2035 – South Australia (Source: Frontier Economics (2021), Potential for gas-powered generation to support renewables)

The optimal level of gas generation was found to be seven per cent of total generation. If natural gas can be substituted by renewable gas into the future, it’s likely that full decarbonisation can be achieved by utilising existing infrastructure and lowering overall costs.

 

Managing the winter lull

Dunkelflaute is a challenging problem that requires detailed planning and mapping of the electricity system and usage throughout the year, rather than relying on averages that are more commonly talked about.

There are a range of technical options available to manage dunkelflaute. Batteries and pumped hydro can be good options for managing hourly and daily fluctuations in demand, but there are questions over longer durations. Shorter-term storage is likely to best be complemented by renewable gas electricity generation to manage longer periods of low variable renewable generation.

Hydrogen efficiency will beat expectations

 From a Twitter thread by Gniewomir Flis

Hydrogen efficiency will beat expectations After spending the last six months looking at cutting edge hydrogen tech I believe that the prevailing view that hydrogen is inefficient needs an update. There’s much innovation to be excited about on the horizon.

Take this T&E [Transport & Environment] chart for instance, which assumes that electrolysis is 76% efficient, and fuel cells are only 54%, which together account for the bulk of the losses. Almost every paper out there uses similar, often worse, numbers.

Current tech is already better than that. For instance, Nel’s stack can be up to 93% efficient (3.8kWh/Nm3 H2). Those numbers are rarely achieved in practice though as the stacks are run at higher current densities (=lower efficiency, but less capex)

But efficiencies are getting better. See the performance of the Oort Energy stack. 90% efficiency at 2A/cm2. This is not some experimental stuff, it’s a full sized stack ready to be manufactured.

In addition to high efficiency, Oort can electrochemically pressurise H2 internally to 200 bar at less than half the energy cost of mechanical compression.

You may also have heard of Hysata which set a record breaking efficiency (98%), though tech is still several years away from commercialisation as it has serious degradation problems.


But more innovation is coming. From the less conventional architectures, we’ve got H2Pro which claims 95% efficiency. So, upcoming electrolysis solutions are looking pretty efficient to me, a step up from the 70-75% efficiencies assumed by many today.

On the fuel cell the innovation is just as good, if starting from a lower baseline (50%). The technology to watch for is high temperature PEM. By high temperature I'm referring to 200C, which aids in rejection of water, a rate limiting step.

Practically, this means that high temperature PEM fuel cells would enjoy a 30% increase in efficiency, i.e from 54% to 70%. Several companies working on this, like Hy-point, Advent, or Mebius. [See this article in Electrive]

Applying these innovations to the T&E chart: Hydrogen production with storage is now 82% efficient.

Round trip efficiency is now 54%, so only 1/3rd less efficient than using electricity directly. Compare with 42% T&E had assumed for… 2050!

And that’s not the end of it. In the storage part, companies like @RuxEnergy (metal organic frameworks) or @VerneH2 (cryocompression) are almost able to match the density of liquified hydrogen without 40% energy loss.Does this change the calculus for hydrogen? To a certain degree. On the road batteries have a significant first mover advantage which I think they’re likely to retain, especially since this up and coming hydrogen innovation won’t get commercialised overnight.


But hydrogen might feel a boost in heavier and infra sensitive applications. I think regional aviation will be a good case in point. Heavy trucking and construction too. Trains could be a good one.


High temperature process heat is another one which would also get a boost. Even if heating with hydrogen is 12% less efficient than with electricity, it may be simpler to repurpose gas infrastructure than it is to lay hundreds of MW of new lines. EU modelling sees a role here.


To conclude: electrolysis is becoming much more efficient than the 70% it gets quoted on. Fuel cells are also getting better. Does this mean we’re all getting FCEVs and hydrogen boilers in 2030? Probably not, but other applications may get a hydrogen boost.


To conclude: electrolysis is becoming much more efficient than the 70% it gets quoted on. Fuel cells are also getting better. Does this mean we’re all getting FCEVs and hydrogen boilers in 2030? Probably not, but other applications may get a hydrogen boost.


Perhaps the real prize here is not that FCEVs are more efficient, but that we will need much less renewable energy to introduce green hydrogen in feedstock applications.

See also his corrections in this thread

The key point is this: producing hydrogen from electrolysis is going to become much cheaper, and hydrogen fuel cells are going to get more efficient. That will mean hard-to-de-carbonise sectors like heavy-duty trucking, air transport and sea transport will be able to switch to hydrogen from fossil fuels. More efficient electrolysis will also make power-to-gas (producing green hydrogen to be later used to make electricity in the grid) will become much cheaper, allowing us to reach the holy grail of long-term storage via methane.

Cheap gas? Not so fast

 Calculations of the cost of different generation technologies show that gas, in the USA, is the third cheapest technology after wind and solar, and certainly much cheaper than coal generation.  However, it is much more expensive in Europe, so there, gas has not replaced coal.  Both have been replaced by renewables.

US & European gas prices, US$ per million BTU
Source: Statista

The reason gas is cheaper in the USA than, say, Europe, is because gas used not to exported from the USA as liquefied natural gas (LNG), but since 2016, LNG exports have grown dramatically.  So the decoupling of US  and global gas prices is disappearing.  But a second factor is also playing out.  US gas prices had been driven lower by fracking.  Yet fracking never made that much financial sense.  Ostensibly, frackers were profitable, but in practice they could only pay dividends by raising new capital.  Wall Street has got more and more skeptical of frackers' cash flows and new money has started to dry up.  On the other hand, if the natural gas price doubles again, fracking might restart.

The chart below shows the gap between European and US gas prices even more clearly.  Note that it is a log scale, which shows just how much gas prices have risen recently.  

Some points.

1. US gas prices are going to keep on rising to closer to European levels, making gas for generation uneconomic in the US.
2. At these prices, the switch to renewables will happen even faster, in Europe and the US.  Not only is gas very pricey, its volatility must be playing havoc with profits.  Renewables are fixed price.  Utilities like that.
3. Synthetic natural gas is likely now cheaper than natural gas in Europe.  Making synthetic natural gas involves a 50% energy loss, but as renewables fall in price and natural gas prices rise ....
4. Gas is very clearly a most unsatisfactory bridge fuel.  Much touted by the oil & gas industry as a "bridge" between the old fossil fuel to a new clean and green one, that little conceit looks implausible now.

Pious hopes

 It's grand that 84% of  CO2 emissions are covered by net-zero commitments.   But we all know about pious hopes for the future.  Yes, I am going to lose weight over the next year.  Yes, I am going to pay down my credit card.  Or perhaps the most famous, by St Augustine: Give me virtue but not yet.  For net-zero targets by 2050 to be credible, we need to see the steps to getting there.  Because the politicians and CEOs who make these grand gestures and pious pronouncements won't be around in 2050 to explain their negligence to angry electorates.  We require annual targets and quarterly emissions reports, just like we have for GDP.

To halve emissions by 2035, which is halfway to 2050, we must cut them by roughly 4.8% per year relative to the previous year.  So how easy is that to do?  

Well, in most countries, unless they have lots of hydro, emissions from electricity generation are ± 25 - 35% of total emissions.  If we replaced our coal power stations by wind, solar and storage over the next 14 years, that would reduce emissions by 2.1% a year. 

But is replacing our entire grid by 2035 feasible?  

New-build wind and solar are much cheaper than new-build coal.  Lazard estimates the cost of  new-build utility-scale solar at US$32.50/MWh, and of new-build wind at $38/MWh, which compares with the cost of new-build coal at $108.50/MWh and even the marginal cost of coal (= operating cost, i.e., excluding the cost of depreciation and interest payments) at $42/MWh.  On my calculations, a grid with 50% wind and 50% solar, plus 4 hrs of lithium-ion storage would produce electricity at $38/MWh which is comparable to the marginal cost of coal.  Is 4 hours of storage enough?  Research using actual weather data and demand (see 96% renewables possible;  A vexed question; and How much storage) suggests that a grid with 50% wind and solar can reliably supply 90% of demand with 4 hours of storage.  This is called "near firm" in the industry.  The remaining 10% will need to be supplied by hydro/gas peaking/power-to-gas.  And by 2035, power-to-gas (no net emissions) will be cost-effective, especially with a price on carbon, which is essential to push the transition and is also certain to occur.

EVs still remain pricey, but their costs continue to decline rapidly, and are likely to reach cost parity within a couple of years.  However, even if we ignore EVs, hybrids deliver a 40-45% cut in emissions, and now cost only a couple of thousand dollars more than old-fashioned petrol/diesel vehicles (ICEVs).  With an incentive of, say, $3000 for all cars with an electric motor (hybrids, PHEVs & EVs) new sales will rapidly transition away from ICEVs.   It will take another 10-15 years for the whole vehicle fleet to switch.   But by 2025 or so, it will be mostly EVs, because they'll have reached price parity then.  So we could reduce emissions from land transport by 90% by 2035.  This would reduce emissions by another 0.6% a year.

Iron and Steel makes up 7% of emissions, and in this sector we have already started to replace coal with hydrogen.  This process should be complete by 2035,  This would cut emissions by another 0.5% a year.   Agriculture contributes 18%, and it is plausible to argue that emissions here could be halved by 2035,  another 0.6% per annum.  Fugitive emissions (gas leaks)  contribute (at least) 5.8% to emissions; they can be eliminated by 2035 -- another 0.4% per annum. 

Together these add up to 4.4% a year, which will cut emissions by 47% by 2035.  

You can see from my back of the envelope analysis that many policies will have to be initiated to achieve a 50% cut by 2035.  Just promising net-zero by 2050 is not enough.  What will be the road map?  How fast will we drive?  How rapidly will emissions decline each year?  Without these details, net-zero proclamations are just greenwashing.   And as long as countries continue to subsidise fossil fuels and refuse to impose a price on carbon, their pious statements of future virtue have no credibility.

Note that gas is twice as expensive outside the USA, making it as expensive as coal.

Methane vs carbon dioxide trade-off

 From And Then There's Physics

There’s a really nice recent paper by John Lynch, Michelle Cain, David Frame and Ray Pierrehumbert on Agriculture’s Contribution to Climate Change and Role in Mitigation Is Distinct From Predominantly Fossil CO2-Emitting Sectors. It’s largely discussing why there are important differences between carbon dioxide (CO2), which is a stock pollutant, and methane (CH4), which is predominantly a flow pollutant.

The basic point is that the emission of CO2 increases the stock, which leads to a long-term increase in atmospheric concentrations and, consequently, to warming that will persist for a very long time. Methane, on the other hand, has a short atmospheric lifetime, decaying within decades to CO2 and water. Given that – for agricultural emissions – the carbon comes from plants, this doesn’t add a new carbon to the system, and hence doesn’t increase the stock. This isn’t strictly true for methane from natural gas, since that does add a new carbon to the system, but this is relatively small when compared to direct CO2 emissions from fossil fuels.

Left: A single emissions pathway (left) reported as CO2-equivalents using the 100-year Global Warming Potential.
Right: How the resulting warming depends on the gas-specific composition (credit: Lynch et al. 2021).

The key figure in the paper is the one above. The left-hand panel shows an example of an emission pathway based on using CO2-equivalents using the 100-year Global Warming Potential (GWP100). The right-hand panel shows the actual warming we would experience for different gas-specific compositions. CO2 warming (dark blue line) peaks when emissions gets to zero, but then remains at this level well after emissions have ceased (it’s essentially irreversible without some kind of artificial negative emission technology).

Methane (yellow line) initially produces more warming than would be expected based on its CO2-equivalence. However, when emissions start to go down, there is cooling, which continues well after emissions have ceased (for completeness, the pink line is 50% methane, 50% CO2, while the green line is N2O which has a reasonably long atmospheric lifetime).

The key point is that if one is using GWP100 to estimate CO2-equivalence, you would predict warming profiles that would be quite different to what would happen in reality. You would under-predict the impact of methane emissions initially, but then over-predict its impact later on.

The reason this is important is because any emission reduction pathways are likely to involve trade-offs. Consequently, as the paper highights,

reducing methane emissions at the expense of CO2 is a short-sighted approach that trades a near-term climate benefit with warmer temperatures for every year thereafter

and

If strong efforts are made to reduce agricultural emissions but prove expensive—in terms of monetary costs, political capital, public goodwill, or individual effort—and detract from efforts to eliminate fossil CO2 emissions then we will be climatically worse-off.

Essentially, the emission of a stock pollutant (CO2) leads to warming that will persist for a very long time, which is different to the impact of a flow pollutant (agricultural methane). The latter clearly does produce warming and, in fact, leads to more warming in the near-term than simple CO2-equivalent estimates would suggest. However, this warming would stabilise if emissions were to stabilise (unlike CO2) and can be reversed if these emissions are reduced (also, unlike CO2).

So, it would seem important to be aware of these differences when thinking of how best to decarbonise. Any strategy that prioritises short-lived pollutants over long-lived pollutants runs the risk of committing us to future warming that is essentially irreversible and that we could have avoided if we’d prioritised differently.

This isn’t to suggest that we should be ignoring the short-lived pollutants. They can have a large near-term impact which may be important if we wish to avoid crossing certain warming thresholds. There may also be other reasons for reducing these emissions (land use change, for example). I just happen to think that if we’re trying to assess the impact of different greenhouse gas emissions, it’s important to use a metric that properly represents this.

Links: (these are additional resources that might be useful)
Agriculture’s Contribution to Climate Change and Role in Mitigation Is Distinct From Predominantly Fossil CO2-Emitting Sectors, new paper by Lynch et al. (2021)
Losing time, not buying time, Realclimate post by Ray Pierrehumbert making the same basic point (from 2010).
Methane, a post I wrote in 2019 about the impact of methane.

This point is contentious, with many accusing those who make it of supporting fossil fuels.  In my opinion, though green methane (made using electricity from wind or solar) is to be preferred to natural gas for 'firming' renewables, natural gas is still preferable to coal, despite leaks ('fugitive emissions') because methane is comparatively so short-lived in the atmosphere.  Especially since coal mining may produce as much methane as extracting natural gas.   So for example, a grid with 90% renewables and 10% gas is in the short-term much worse for global warming than a 100% coal grid, but in the longer term is 95% less warming.  

The real problem would be a huge and sustained expansion in methane leaks, because that would mean continually rising methane levels in the atmosphere.  Stable methane emissions would lead to stabilised methane levels in the atmosphere within 10 years, with no additional warming (from the methane) after that.   The implication is that we should accept legacy gas power stations in our grid as we replace coal while we wait for cheaper long-term storage options to become available, including power-to-gas (green methane). 

The IEA's coal phase out

 A key to cutting emissions is to stop burning coal.  Just doing that will cut global emissions by 30%. 

From EMBER

As envisioned in the IEA roadmap, achieving net-zero energy emissions globally will be led by a clean electricity revolution, due primarily to the relatively high level of technology readiness of the electricity industry and the growing attractiveness of electricity as an option for decarbonising other sectors, either directly or indirectly.

Some key milestones for this revolution, as set out in the IEA roadmap, include: no new unabated coal plants approved for development after 2021; global phase-out of subcritical coal power plants by 2030; and achieving 100% clean electricity in advanced economies by 2035 and globally by 2040. 

To achieve the above-noted milestones requires, according to IEA, a massive step-up of global wind and solar additions to over 700 GW per year over the next 30 years, from its current levels (about 250 GW in 2020). Other low-carbon generating technologies, especially hydro, nuclear, and bioenergy, are also expected to experience a rapid expansion, to meet about 12% of the global electricity needs by 2050. Besides, some energy technologies (e.g., hydrogen, and carbon capture, utilisation and storage, CCUS), that are currently in the demonstration or prototype stage, also need to expand rapidly, especially after 2030, to decarbonise the global electricity industry.

To achieve net-zero by 2050, developed countries (OECD in the chart above) will need to phase out all coal and gas by 2035.  Or it will have to abate all carbon emissions using carbon capture and storage (CCS) which is unlikely giving its cost.  Developing countries will need to achieve net-zero electricity by 2040.  It is also vital that no new coal power stations be approved for development, starting from now.

The chart doesn't show battery storage requirements, but by 2030, we will prolly need 4 hours of storage, supplemented by EV batteries and power-to-gas

Scotland reaches 97% renewables

 From The BBC.

Scotland has narrowly missed a target to generate the equivalent of 100% of its electricity demand from renewables in 2020.   New figures reveal it reached 97.4% from renewable sources.  This target was set in 2011, when renewable technologies generated just 37% of national demand.

Industry body Scottish Renewables said output had tripled in the last 10 years, with enough power for the equivalent of seven million households.  Chief executive Claire Mack, said: "Scotland's climate change targets have been a tremendous motivator to the industry to increase deployment of renewable energy sources.  "Renewable energy projects are displacing tens of millions of tonnes of carbon every year, employing the equivalent of 17,700 people and bringing enormous socio-economic benefits to communities."

In 2019 Scotland met 90.1% of its equivalent electricity consumption from renewables, according to Scottish Government figures.  Scotland has some of the most ambitious climate targets in the world, with its Climate Change Bill setting out a legally binding target of reaching net-zero emissions by 2045.  By 2030, ministers want renewable energy generation to account for 50% of energy demand across electricity, heat and transport.

Ms Mack, added: "Domestic and commercial transport accounts for almost 25% of the energy used in Scotland, with heat making up more than half, as well as more than half of its emissions.  "Currently 6.5% of our non-electrical heat demand is generated from renewable sources.  Industry and government must continue to work together if we are to fully realise our potential to meet net-zero by 2045."

The next steps on the road to zero carbon will be carbon-neutral gas for heating, and electric vehicles.

Getting to zero carbon in Germany

 From a Twitter thread by Philipp Litz:

Germany plans on going climate neutral by 2050 the latest. Most of the electricity produced will come from wind and solar. But what is the strategy on keeping the lights on, when there is no wind and sun, and coal, natural gas, or oil plants will be phased out?

First: There will still be plenty of dispatchable capacity. However, these will not be nuclear, coal or classic natural gas power plants, but primarily small, decentralized gas units that are operated with (green) hydrogen.

Second: Pump and battery storage (both stationary and mobile in cars) are becoming increasingly important. They store excess electricity in times of high wind and PV generation and make it available when it is needed. In addition, traditional demand is becoming more flexible.

Third: The European electricity market will grow even closer together than today. This means you can take advantage of balancing effects of renewable energy generation. Also, sharing backup capacities makes it cheaper for everybody.

Wind & solar now 10% of global electricity

 From EMBER

This report shows evidence that wind and solar have quickly increased to become a major source of electricity in most countries in the world, and are successfully reducing coal burn throughout the world.

Ember’s new half-year analysis aggregates national electricity generation for 48 countries making up 83% of global electricity production. It builds on Ember’s annual Global Electricity Review, released in March 2020. 

Main findings:

• Wind and solar generation rose 14% in the first half of this year (H1-2020) compared to H1-2019, generating almost a tenth (9.8%) of global electricity. In the 48 countries analysed, wind and solar generation rose from 992 terawatt hours in 2019 to 1,129 terawatt hours in H1-2020. That meant wind and solar’s share of global electricity has risen from 8.1% in 2019 to 9.8% in H1-2020; and their share more than doubled from 4.6% in 2015, when the Paris Climate Agreement was signed. Wind and solar generated almost as much CO2-free power as nuclear power plants, which generated 10.5% of global electricity in H1-2020 and whose share remained unchanged from 2019.
• Many key countries now generate around a tenth of their electricity from wind and solar: China (10%), the US (12%), India (10%), Japan (10%), Brazil (10%) and Turkey (13%). The EU and UK were substantially higher with 21% and 33% respectively; within the EU, Germany rose to 42%. Russia is the largest country so far to shun wind and solar, with just 0.2% of its electricity from wind and solar.
• Global coal generation fell 8.3% in the first half of 2020, compared to H1-2019. This breaks a new record, following on from a year-on-year fall of 3% in 2019, which at the time was the biggest fall since at least 1990. The fall in H1-2020 is because electricity demand fell globally by 3.0% in H1-2020 due to COVID-19, as well as due to rising wind and solar. Although 70% of coal’s fall in H1-2020 can be attributed to lower electricity demand due to COVID-19, 30% can be attributed to increased wind and solar generation. The US and the EU are racing to reduce coal, with falls of 31% and 32% respectively. China’s coal fell only 2%, meaning its share of global coal generation rose to 54% so far this year, up from 50% in 2019 and 44% in 2015.
• Wind and solar have captured a five percentage points market share from coal since 2015. Coal’s share fell from 37.9% in 2015 to 33.0% in the first half of 2020, as wind and solar grew from 4.6% to 9.8%. India’s change was even more dramatic: wind and solar’s share rose from 3% of total generation in 2015 to 10% in the first half of 2020; at the same time, coal’s share fell from 77% to 68%. For the first time, the world’s coal fleet ran at less than half of its capacity this year.
• The global electricity transition is off-track for 1.5 degrees. Coal needs to fall by 13% every year this decade, and even in the face of a global pandemic coal generation has only reduced 8% in the first half of 2020. The IPCC’s 1.5 degree scenarios show coal needs to fall to just 6% of global generation by 2030, from 33% in H1-2020. The IPCC shows in all scenarios most of coal’s replacement is with wind and solar.

The question is whether wind and solar will grow exponentially or not.  The percentage from W&S has risen from 4.6% in 2015 to 9.8% in 2020, which is roughly 1% per year.  At that rate, it will take 38 years for coal to fall to zero (coal provided 38% of the world's electricity in 2018).   But if the percentage grows at the same rate as it did from 2015 to 2020, which is about 15% per annum, or doubling every 5 years, by 2025, wind and solar will make up 20% of global electricity generation.  By 2030, if growth is exponential, it will make up 40%, more than replacing coal.  

Why should growth be exponential not linear?

1. To date, since 1990, it has been, though the growth rate has slowed a little.  Why won't that continue?  It's a classic learning-curve.  As installations grow, costs fall, making installations grow even faster, and costs decline even faster.
2. Up until just a couple of years ago, renewables were more expensive than new-build coal, but now they are cheaper, and will go on getting even cheaper still.  In many places, the costs of new-build wind and solar are the same as or below the operating costs of coal.  There are powerful commercial reasons now to switch away from coal.
3. The EU's carbon price has risen sixfold over the last three years, as the EU has finally started tightening supply of permits.  There is very strong support within the  EU for imposing a carbon price on the embedded carbon in imports to the EU from countries which do not themselves have a carbon price.  No doubt there will be ructions and appeals to the WTO and possibly retaliation.  But the EU is making a sterling effort to reduce emissions.  If they don't price embedded carbon in imports, their carbon price will just lead to emissions being outsourced to countries (free riders) which don't tax carbon.  For example, an EU steel producer would be disadvantaged compared to a Chinese or Russian producer.  Applying a carbon price to imports, and exempting imports from countries which also have a carbon price will provide a powerful incentive for countries without a carbon tax to introduce one.  And these non-EU countries will apply it in turn to embedded carbon in their imports, creating a cascading shift to pricing carbon globally.  
4. So not only will renewables make inroads into coal because of the learning-curve cost declines as installations increase, but coal and oil and gas (at half the rate, but that may be too low) will increasingly pay a carbon price in addition to already unfavourable costs relative to renewables. 

Thus it seems very plausible to me that installations of wind and solar will continue to grow exponentially.  Which implies that coal will be more or less out of global electricity generation by 2030, followed by gas (unless it is synthetic natural gas, made via the Sabatier or similar process.)

Good news for the climate.

Source of basic data: IEA

Gas peakers stranded assets by 2030

Source: Vox -- Clean energy is catching up to natural gas.The natural gas “bridge” to sustainability may be shorter than expected.

From IEEFA:

Europe’s power system will look very different in 2030, with energy storage supporting the “dominance” of wind and solar generation, according to new research from Wood Mackenzie.

The big five European markets—Germany, the U.K., France, Italy and Spain—will get the majority of their power from wind, solar and other variable renewable energy sources as early as 2023, WoodMac says. By 2040, Europe is expected to add another 169 gigawatts of wind and 172 gigawatts of solar.

As that variable output surges, Europe has four options for balancing out its grid: pumped hydro, gas peakers, energy storage and interconnectors. Only the final three of the quartet are likely to be the focus of new investment.

For now, “gas peakers are more essential than ever,” said Rory McCarthy, Wood Mackenzie principal analyst. “They can ramp up to full output from warm in a couple of minutes for modern systems, have increasing efficiency levels at part loading and boast unlimited duration, assuming a reliable gas supply.”

But by the end of the decade, battery storage will be the cheapest option for balancing Europe’s grid, overtaking gas peakers, according to a new long-term energy storage outlook. Europe’s energy storage capacity across all segments is expected to grow from 3 gigawatts today (excluding pumped hydro) to 26 gigawatts in 2030—and 89 gigawatts by 2040.

“By 2030 energy storage will beat gas peakers on cost across all our target markets, resulting in a cloudy outlook for any new future peaking turbines,” McCarthy said. “Fuel and carbon prices are on the up, technology costs are not set for any major decreases and net-zero policies will eventually target the decarbonization of all power market services.”

The moral of the story:  we should keep existing gas power stations whle we wait for battery prices to fall even further, but not build new ones.  Unless we use synthetic natural gas, or green methane, produced via the Sabatier process using green hydrogen made from electrolysing water using renewable electricity.  And perhaps not even then.

90% renewable by 2035

From IEEFA:

It will be feasible to power the U.S. on 90 percent clean electricity by 2035 thanks to stunning declines in the costs of renewables, a new study finds.

In just a few years, decarbonizing the grid went from a solar-lover’s pipe dream to something many major American utilities have committed to, from Southern Company to Duke Energy. But utilities typically pick a midcentury deadline, as do states that have passed such goals. That puts execution comfortably beyond the tenure of anyone in power today. 

The new study, from UC Berkeley and GridLab, raises the stakes considerably. By using updated cost figures for wind, solar and batteries, the researchers found that it will be economically feasible to power a reliable grid by 2035, while only depending on natural gas for 10 percent of annual electricity production.

This scenario retires all coal plants by 2035 and does not require any new construction of gas plants. The cost of wholesale electricity would be 13 percent lower than it is today, in contrast to the common assumption that a shift to clean energy would radically increase expenses.

Cheaper, cleaner power without loss of reliability may sound too good to be true. But that’s what the study’s numbers suggest: Clean energy has become so cheap already that all prior predictions of future scenarios need a massive revision.

Setting the target at 90 percent clean removes the need to run the system only on renewables at all times; it can burn a little gas when absolutely necessary. This proved durable for meeting demand in every hour of the seven years modeled in the study to test reliability under annual variations in weather.

[This gas could be produced by using surplus renewable electricity to make hydrogen via electrolysis and then methane via the Sabatier process.]

Getting to zero carbon

In order to avoid a rise of more than 1.5 degrees C in global temperatures, we need to cut emissions of CO₂ to zero by 2050.   Which implies we need to cut emissions by 50% by 2035, which is halfway to 2050, and by 1/3rd by 2030.  At first sight, it seems an impossible task, but if you look closer, it's not nearly so formidable.

This is an informative chart from Climate News Network.  Note that the chart only covers CO₂ emissions, not methane, so it doesn't include agriculture (see Lab grown food will save the planet).

So, let's start with the largest emissions: base-load electricity, which is 1/3rd of CO₂ emissions.  Wind and/or solar are now the cheapest sources of bulk electricity almost everywhere in the world.  In China, the operating cost of coal is now about the same as the new-build cost of solar.  And the costs of renewables continue to fall.  My forecast is that by 2035, and prob'ly by 2030, there will be very  few coal-fired power stations left.  Not only will they cost much more than wind or solar, but there will be carbon pricing in most large  countries, and those carbon prices will be applied to imports from countries which do not themselves have carbon pricing.  The coal power stations being now planned and built in China and other east Asian countries will be stranded assets.  It's possible that their governments will subsidise coal power stations either directly or by forcing utilities to buy their output and consumers to pay the (much) higher costs of superannuated coal power stations.  However, see carbon pricing, above.   So, in the West, no coal power stations.  In China, perhaps some, heavily dependent on subsidies.  But even there, commercial reality will be compelling.  It will prob'ly be cheaper just to buy out old coal power stations and close them down than to continue subsidising them.  So, by 2030, perhaps 80% of baseload electricity replaced by renewables, by 2035, 95%?

The next biggest is "variable electricity".  What they mean by this is gas-peaking power stations, designed to run for a couple of hours each day when demand peaks.  The demand for gas peaking has increased as renewables penetration has risen.  But these too are under threat.  Battery costs are falling by 20% per annum.  Already, in much if the world, battery peaking is cheaper than gas peaking.  As battery costs fall, and as the cost of renewables falls (renewable electricity being what charges the batteries for later discharge during peak demand), the cost disadvantage of gas peaking compared to battery peaking can only worsen.   By 2035, we will only keep gas peaking plants for extremes, when it's mid-winter, the skies are grey, and there is no wind for days at a time.  And the gas we use to fuel them will be green methane, produced by surplus renewable electricity via electrolysis of water and the Sabatier process.  So, another 12% of CO₂ emissions removed by 2035.  That's a total so far of a 44% reduction.

Short-distance light road transport is the next largest sector, at 11%.  The battery cost decline is critical here too.  Already, ordinary, old-fashioned hybrids cost just a couple of thousand dollars more than their petrol equivalents, and plug-in hybrids another couple of thousand more than non plug-in hybrids.  Just switching to hybrids will cut emissions from light transport by more than half by 2035.  Yet full EVs will trump hybrids by 2030, because the cost of batteries will have fallen by 90% by then.  EVs will make up the majority, perhaps almost all of car and light-truck sales by 2030.  Since the car fleet will take time to shift, not all 11% of emissions produced by cars will be gone by 2035.  But surely, most will be. 

There's our 50%.  But wait—there's more!  Heavy road transport will also be electrified.  Iron and steel will be made with green hydrogen.  Air transport, shipping, long-distance road transport will all be using synthetic fossil fuels, or will be electrified.  Heating will be electrified, or will use synthetic natural gas (green methane).  In other words, we could cut CO₂ emissions by 75% by 2035.

That still leaves agriculture.  Methane is 100 times at effective a greenhouse gas as CO₂ and the burps and farts of ruminants (cows/sheep/goats etc) are rich in methane.  As I've said before, we won't be eating "real" meat by 2035.   And as we mine less coal and use less gas, atmospheric methane will decline rapidly.  The bad news about methane is its strong greenhouse gas effect.  The good news is that it rapidly decays into CO₂ in the atmosphere.  Agriculture is also, potentially, a key way we can remove CO₂ from the atmosphere.

It's easy to be pessimistic about global heating.  Yet, everywhere you look, there are encouraging signs that we can reduce emissions.  As global temperatures rise, and the consequences of global heating get more obvious, the political pressure to act will become irresistible.  Combined with the falling costs of renewables and batteries, that will mean that the logjam will suddenly shift, and we will move into a period where  CO₂ emissions will start to fall rapidly year by year.  It's prolly too optimistic to hope that emissions peaked in 2019, even though the covid crash has slashed emissions this year.  But as the world economy recovers, driving up emissions, so also will the world refocus on the climate catastrophe.  The shifts to renewables in electricity generation, and to electrification in transport are unstoppable, now.  And success here will encourage action everywhere. 

My confident prediction: by 2035, emissions will have fallen by way more than 50%, and we will be starting to tackle the harder sectors like cement and agriculture.