96% renewables possible

 From a Twitter thread by David Osmond, a wind engineer at Windlab

A common riposte by fossil-fuel spruikers to claims that we can get  to 100% renewables is that it is impossible.  David Osmond has done a simulation using actual data for wind, sunshine and demand in Australia's NEM (National Electricity Market) over a 3-year period which shows that we can get to 96% (including existing hydro) without difficulty.  The precise numbers will differ for each genertion region, but in principle, this analysis implies that similar percentages can be reached in any continent-wide grid.  ("Island" grids, i.e., grids not connected to other geographies, will require more storage)

Summary of my 96% renewable NEM simulation, as presented at ANU's 100% renewable workshop.  My data is based primarily on actual wind & solar generation data, using 3 yrs of data at 30 minute resolution.  It uses 24GW/81GWh of short-term storage plus Snowy2.0. 

Actual wind and solar generation has been scaled up to 38 GW of wind, 16 GW of utility PV and 35 GW of rooftop PV.  Also assumed a completed NSW-SA interconnector, Stage 1 of the Marinus cable to TAS, and the medium upgrade of the NSW-QLD interconnector. 

The remaining 4% came from "other".  In the short to medium term, "other" is likely to mean gas or demand management.  But in the longer term it could transition to biofuels/biogas, long-term storage such as Tasmania's battery of the nation, or a hydrogen based source.

During days of poor wind and/or solar resource, existing hydro and/or Snowy2.0 is run hard, which makes up much of the shortfall.  "Other" is used to fill the remaining shortfall. 

For the 24GW/81 GWh of short-term storage, it's worth noting that we already have ~1.4GW/25GWh from the existing pumped hydro projects at Tumut3, Shoalhaven & Wivenhoe.  The remainder could come from 3 million residential batteries and a small fraction of an EV car fleet. [On my (NPT's) calculation this is about 4 hours of storage]

QLD is a particularly important state, due [to] the relatively good performance of its wind on calm wintery days in the southern states. Its solar also performs relatively well on those days too.

Finally, note the negative correlation between Mt Emerald wind and solar/wind in every other state, at both 30-minute & daily timescales.  Nth QLD is particularly important to a mostly renewable NEM!

The full presentation is available at ANU's 2020 100% renewable workshop webpage.

One more tweet for @simonahac  & @gnievchenko

 A graph of the curtailed generation.  If we were able to send the curtailed generation to a hydrogen electrolyser, then the 2nd graph shows the capacity factor of that electrolyser, and how much of the curtailed power it could use.

Green shoots in a coal valley

There are two aspects to replacing a coal power station (often located next to the coal mine which supplies it). 

The first is replacing the power it used to generate.  I've talked about this a lot.  A mixture of wind plus solar with 4 hours of storage will replace baseload power, though we will need more storage, or gas, for renewable percentages higher than 80%.

The second is the human dimension.  Power station and mine workers will lose their jobs.  Communities will lose people, and unemployment rates will climb.   The best would be for the coal power station and mine to be replaced by the new renewable facility at the same place.

This is exactly what's happening in Victoria.  The LaTrobe valley in Victoria is where most of Victoria's electricity used to be generated, from vast fields of brown coal (lignite).  Hazelwood, a lignite-burning power station just 30 km from where I now live, was closed down by its French owners two years ago, with little warning.  The future for the valley looked bleak.  It already had high levels of unemployment, thanks to the privatisation of the old state-owned SEC (State Electricity Commission).  And although there are excellent wind resources along the coast, there's less wind inland. 

But the future looks a lot brighter now:

At exactly 5pm on 29 March 2017, Unit 1 of the Hazelwood station reported the last energy generation after 53 years of faithful operation. Hazelwood isn’t the first coal power station to close in recent years — in fact it is one of 13 that closed over a five year period — but, as one of the largest and dirtiest power stations in the country it has become totemic, for both the environment movement and Australia’s coal fetishists.

Now, two years on, fears of mass workforce dislocation — such as the Latrobe Valley suffered when the region’s power stations were privatised in the 1990s — have largely failed to materialise. More than 1,000 jobs have been created in the region and unemployment has dropped from 8% to 5.7%, in no small part due to the efforts of the Latrobe Valley Authority, set up by the state [Labor] government to help ensure a “just transition” for the workers and local community.

The failure of three coal units through the heat of 25 January this year kicked off a series of rolling blackouts in Victoria and provided yet another reminder of the age and fragility of the state’s coal power generators.

Despite widespread acknowledgment of the inexorable decline of coal power, there are plenty of signs that Latrobe Valley’s proud role as an energy region will outlive the area’s three remaining coal power stations. Reskilled workers have found work in the region’s booming solar energy sector, and many more jobs will be created if proposals progress for a massive offshore wind farm and a waste-to-energy project — though concerns have been raised around the environmental credentials of the latter.

Solar Victoria, the authority set up to oversee the state government’s policy to install solar in 700,000 households, has been set up in Morwell, and the coal town will soon be welcoming SEA Electric, an Australian electric vehicle manufacturer that intends to employ 500 workers locally.

There’s even an embryonic proposal to harness the strong local grid, nearby Thomson reservoir and favourable topography for a pumped hydro project that could be significantly cheaper than Snowy 2.0.

Standing out among the list of energy proposals is the newly announced Delburn Wind Farm, a 300MW windfarm that would be under three kilometres from the mine that fed Hazelwood, at the northern end of the Strzelecki Ranges.

If the proposal goes ahead, not only would it massively boost clean energy production in the east of the state, it would be the first windfarm in Australia to be built in a plantation forest.

While windfarms have co-existed well with agricultural operations for decades, outside of northern Europe, windfarm developers have overlooked plantation forests. State planning regulations that prohibit secondary uses for plantation lands as well as wind turbulence caused by trees have, until now, ruled significant parts of regional Australia out of consideration.

Thanks to newer designs that utilise very tall towers, wind turbines can now be built well above the choppy wind immediately above the forest canopy. The Delburn Wind Farm intends to utilise hybrid concrete and steel towers up to 160m tall supporting the 5.6 MW turbines expected in the market in the early 2020s.

The Delburn Wind Farm is expected to generate 980GWh annually, as much power as used by approximately 200,000 average Victorian homes. Just a few years ago a windfarm with this capacity would have required up to 160 turbines, but with larger generators, 90m blades and topping out at 250m tall, only 53 turbines will be required for the same output.

While the wind in the Latrobe Valley is not the best in the state, the site has a number of advantages. The nearby grid connection, a legacy of Hazelwood, is unconstrained, avoiding a growing problem for wind and solar developers around the country. The windfarm is subject to wind regime different from that experienced by the concentration of windfarms in western Victoria, and as a result it will enjoy periods of generation when other windfarms aren’t generating, an advantage in the market.

As a working plantation forest, 90% of the roadways required for the windfarm already exist and the windfarm operation will have minimal impact on existing forestry operations. Situated entirely within a pine plantation monoculture, the impact on local fauna and flora will be negligible.

Like a growing number of windfarms, the Delburn Wind Farm proposes to allow community co-investment, make payments to neighbours and set up a fund to support the local organisations that are critical to maintaining the social fabric of regional communities.

[Read more here]

The very rapid growth of rooftop solar (up nearly 50% or 500 MW this year) will be sufficient complement to the new wind capacity to provide reasonably stable power.  A pumped hydro project at the nearby Thomson dam would provide "firming". 

Good news.

Source: The Guardian

Wild is the wind

The resource that could power the world.

A wind turbine blade at the Siemens Gamesa factory in Hull.  Source: The Guardian

A fascinating article from the Guardian:

The wind rips along the Humber estuary in Hull. It’s the kind that presses your coat to your back and pushes you on to your toes. “A bit too windy,” shouts Andy Sykes, before his words are swept away. He is the head of operational excellence at the Siemens Gamesa factory, which supplies blades – the bits that turn – to windfarms in the North Sea. At 75 metres long, they are hard to manoeuvre when it’s gusting.

Inside the vast factory hall, the blades lie in various states of undress. Several hundred layers of fibreglass and balsa wood are being tucked into giant moulds by hand. There are “naked” blades that require paint and whose bodies have the patina of polished tortoiseshell. Look through the hollow blades from the broadest part, and a pale green path, the tinge of fibreglass, snakes down the long tunnel, tapering to a small burst of daylight at its tip.

“Alice in Wonderland,” Sykes says. “That’s how I feel. That’s the emotion coming through. It’s 75 metres long. We know that. But stood here the perspective is just fantastic. It’s my favourite view.” Down this strange green rabbithole is a glimpse of a greener future, the possibility of a world powered by wind.

This is not as fanciful a vision as it once seemed. In the UK, the wind energy industry is celebrating. Last month, the cost of renewable energy dropped dramatically to undercut by almost half the government’s projections for 2025. At £57.50 (US$73) per megawatt-hour (MWh)[for offshore wind], it is far cheaper than the state-backed price of £92.50 awarded in 2016 to Hinkley nuclear power station. The speed of wind’s progress is extreme and inarguable.

The wind energy sector is certainly booming. Across the river from the Siemens Gamesa factory in Hull, in this long windy corridor of development on the east coast of the windiest country in Europe, there’s the Dong Energy hub, the screens of its operation room flickering with the data of wind captured by blades turning in the North Sea. Next month, the company will change its name – short for Danish Oil and Natural Gas – to Ørsted, after the celebrated Danish scientist who discovered that electric currents create magnetic fields, to reflect its near complete shift from black energy to green.

Dong was among the companies that achieved the landmark price of £57.50, and Emma Toulson, who works in their Grimsby office, explains how they did it.

Since the government ruled out new onshore windfarms in England – a promise in its 2015 manifesto – energy companies have been forced offshore, making the UK the world’s offshore leader. Allowed to develop beyond the vision of land-dwellers who see windfarms as a blot on the countryside, the turbines have grown steadily larger, as have the farms to which they belong. Dong’s Hornsea Project Two will span 480 sq km, and Toulson’s PowerPoint outlines a large jagged blue diamond for Project Three and an even larger blue rocket shape for Four.

Toulson has a slide that shows one very clear reason for the falling cost of wind energy. Over time, the diameter of the blades have enlarged. A turbine commissioned in 2002 swept 80 metres; in 2005, that figure rose to 90 metres; in 2011, it was 120 metres. By 2020, it will be 180 metres.

Of course, the supply chain has improved, and there have been engineering refinements. But put baldly, wind energy costs less, and will go on costing less, because the turbines are growing taller and the blades longer. The manufacturers of these machines are in a race to produce the largest.

And yet despite the size of its gargantuan machines, the offshore wind industry is still in its infancy. Wind turbines may look alike, but as Garrad points out, “we are a long way from a design consensus”. There are fixed turbines and floating turbines, which can access deeper seas, turbines with gears and turbines without. The sight of three blades harmoniously turning has become commonplace. But there is no reason why offshore turbines should look like this. They could operate with a single blade (ruled out on land because one blade, whirring faster, is noisy), or with two blades (ruled out on land because an optical illusion makes them appear to pause as they pass the tower, flummoxing passersby). Offshore, there would be only the gulls to offend, and the people who will live, in four-weekly shifts, on the new accommodation vessels that are being deployed to manage the farms’ growing distance from shore.

Ken Caldeira is one of the two Stanford climate scientists behind the idea of a North Atlantic windfarm the size of India. To understand the significance of his discovery, he says, it is important to know that when wind turbines are arrayed in rows, the extraction of wind by the first row reduces the amount of wind available for the second row, and so on. Row by row, the wind’s potential diminishes.

To counter this effect, turbines need to extract energy from the wind that’s above them. What Caldeira found was that that is exactly what can happen in parts of the North Atlantic, where heat “pours out of the ocean”, causing greater “cyclonic activity”. But could a farm the size of India really be built in open ocean? “You wouldn’t want to,” he says. Better to have many very large ones (China currently has the largest). A wind power station that size “would be a climate change in itself”. For one thing, “pulling that much energy out of the sky shifts the direction of wind”.

“The total amount of power in winds globally is something like 50 times bigger than the total amount of power used by human civilisation,” Caldeira reckons. “If we were to power civilisation by winds, we would need to capture about 2% of winds today,” he says

[Read more here]

Elon Musk has said that the whole USA could be powered by a 100 by 100 mile square somewhere in the south west of the country, and the battery storage to "firm" that would require just 1 square mile.  The USA covers 3.8 million square miles.  In other words,  only 0.26% of the US's land area would be used for solar panels.  And that doesn't even count rooftops!

Area needed to power the whole US by solar.  Source: Inverse

The moral is clear: we have more than enough wind and solar resources to run our economies.  Because solar requires more storage than wind and because wind and solar are complementary (for example, the wind is stronger in winter when the sun is weaker), a blended grid with both wind and solar is the cheapest option.  To that we'll add some battery storage, some pumped hydro, and some concentrated solar power (CSP), and perhaps, in high latitudes, power-to-gas.

Pumped Hydro is cheap

Kidston pumped hydro.  Source: RenewEconomy.

There are three pumped hydro projects either in a late planning/funding stage or already under construction in Australia.  (Snowy 2.0, which might potentially be a very large fourth pumped hydro project still seems to be at the air bubble phase)

Pumped hydro can store power like a battery.  When electricity is plentiful or demand is low, water is pumped uphill into a dam.  When demand is high, the water flows back downhill and turns the turbines, generating electricity which is fed into the grid.  It's easy to confuse conventional hydro with pumped hydro.  Conventional hydro "uses" the water once: it flows through the turbines and away.  Pumped hydro re-uses the water, again and again.  The only losses are via evaporation.  Pumped hydro dams are about 1% of the size of conventional hydro dams.  Unlike conventional hydro which can produce continuous baseload generation, or, if needed, dispatchable generation up to the maximum capacity, pumped hydro power plants will only produce power when it's needed, for a few hours each day.  Because pumped hydro only needs small dams, there are far more suitable sites than is the case with conventional hydro.  And pumped hydro is a cheap form of storage.   Molten salt storage is also cheap, but only when it's part of a CSP plant. Pumped hydro on the other hand can be used for wind, solar and even baseload (to handle demand variations.)


The three projects are at Kidston in northern Queensland, Oven Mountain in NSW, and  Cultana in South  Australia, which will be the first salt-water pumped hydro in Australia.

Let's compare the projects.  I've also included Tesla's South Australian "big battery" for comparison.

Right now, pumped hydro is still a lot cheaper than li-ion batteries.  Even assuming that battery prices fall more slowly (20% p.a.) over the next 5 years than they did for the last 3 (30% p.a.) then  li-ion battery storage will be close to pumped hydro in 5 years.  But as I've said before, diversification in both sources of supply and sources of storage is sensible, because it reduces risks.

Wind plus solar hybrid update

I talked about Windlab's hybrid wind/solar/storage Kennedy "energy park" here.  Cleantechnica has an update:

A world first renewable energy project has taken its first steps in Australia, with big-name companies Vestas, Tesla, and Windlab backed by Australia’s Clean Energy Finance Corporation partnering on a $160 million, 60 MW hybrid wind, solar, and energy storage project.

A flurry of announcements were published Thursday confirming the development of a 60 MW (megawatt) hybrid wind, solar, and energy storage by Australia’s international wind energy company Windlab. The AUD$160 million Kennedy Energy Park set to be built in central north Queensland as a joint venture between Windlab and Eurus Energy Holdings Corporation of Japan.

Kennedy Energy Park will be the first wind, solar, and storage hybrid generator connected to Australia’s national electricity network via a single connection point. It also serves as an industry-leading project demonstrating the complementary nature of the three technologies and proving their ability to work together. Vestas — who will provide the wind turbines for the project — describes the project as a “world first” of its kind.

The Kennedy Energy Park will consist of 43.2 MW worth of wind, made up of twelve Vestas V136, 3.6MW turbines; 15 MW worth of AC, single-axis tracking solar; and a 4 MWh Li Ion battery storage provided by Tesla.

Upon completion, Kennedy will be able to generate approximately 210,000 MWh of electricity per annum, which is the equivalent of enough electricity to supply over 35,000 average Australian homes.

[Read more here]

I estimated that they might need 3 hours of storage, but in fact they will have only about 10 minutes' worth.  Although the battery storage is enough to stabilise short-term fluctuations in output, it's not enough to provide the "load shifting" needed for the evening peak in demand.   I presume that the cost of battery storage remains a limiting factor.  To provide true baseload, they will need more storage, to wit, 72 MWh.  However, the new Kidston pumped hydro storage in N Queensland (a couple of hundred k's west of Kennedy) will have 2000 MWh of storage (more on that in a later post)

(As an aside, the last paragraph in the quote above suggests a daily household use of electricity of 16.4 kWh, a tad higher than my previous estimate of 15.9 kWh.  The shorter-range Tesla Model 3 will have a 50 kWh battery pack or 3 days' worth of power for the average Ozzie house.  The Tesla home battery, the Powerwall, has 13.5 kWh of storage, or enough to cover 19 hours of demand.  I suspect that most of the battery storage in Australia will initially be behind the meter)

We have a fighting chance

Emissions have probably peaked, or will soon, but that still means that the level of CO2 in the atmosphere continues to rise, because we are still adding to it faster than natural processes can remove it. To stop the level in parts per million of CO2 in the atmosphere from rising, we have to reduce emissions by at least 80%.  Maybe more, because the natural "sinks" which absorb CO2 are full--the world's seas, for example are already turning more acidic.

Source

The good news is that emissions are about to start falling.

Renewables are getting progressively cheaper, and are steadily replacing coal.  The total costs of new renewables (without "firming") are now at or below the total cost of new coal and gas. Over the next 10 or so years, BNEF reckons that the total cost of new renewables will fall below the operating cost (mostly fuel and maintenance) of existing coal and gas power plants.  At that point, coal and gas power station shut-downs will be limited only by the cost of "firming", i.e, the costs of making variable wind and solar as "firm" as supply from baseload power stations which burn coal, gas or uranium.  And the costs of batteries, concentrated solar power (CSP) are falling fast, and there is always the 100 year old technology of pumped hydro storage.  Some estimates show that the cost of pumped hydro is as low $20/MWh.  CSP is coming at at $60-$70/MWh for power plus storage: "firm" (i.e. baseload) plus dispatchable capacity.  And you don't need 100% backup for variable renewables.  In most places 25% will do, so you will be able to combine cheap wind and solar with some storage and get baseload output more cheaply than from coal and gas.  At that point, existing coal and gas power stations will be rapidly and completely replaced with renewables.

(Source)

For the first time, mid-priced electric cars are available, and China (responsible for 1/3rd of global CO2 emissions) has tough new standards to reduce the sale of petrol/diesel vehicles (ICEVs). France, UK, Holland, Austria and now California are contemplating or planning a ban on petrol/diesel car sales from 2030 onward.  By 2022 or so, EVs will have the same "sticker price" as ICEVs, but they are far cheaper to drive.  By 2030, or before, 100% of car and light van sales will be electric.

Source

There remain some hurdles--agriculture, burning forests/scrubland, cement and iron and steel production, jet travel. But even together, these are smaller than transport and electricity generation combined. If we can convert electricity production to renewables/nuclear and can electrify our car/truck fleet, we have a fighting chance.

But there is a race between de-carbonising our economy and the rise in world temperatures.  As long as atmospheric CO2 keeps on rising, so will average world temperatures.  And CO2 will only stop rising when CO2 emissions have fallen at least 80%.

Global temperatures are rising by 0.2 degrees C per decade. The rise may be accelerating--let's hope that it's not.

Source NOAA

Let's say it takes us 20 years to move to 100% renewable electricity. Hydro+renewables are now 22% of world electricity supply, which means we need to target a 4% per annum switch, but it will likely be slower in earlier years and much faster towards the end.  That means that global temperatures will rise by another 0.4 degrees.

Cars will take longer. As I said, we'll prolly get to 100% electric sales by 2030, maybe earlier, but cars last a long time (I've seen data varying between 11 and 20 years, depending on the country) If it's 20 years, we won't have a 100% car fleet till 2050. That means temps will rise another 0.2 degrees. So by 2050 we will end up 0.6 degrees above 2016, 1.8 degrees (?) above the pre-industrial average. Plus there are built in lags in the system's response to forcing which will cause temperatures to go on rising for a few decades even with zero emissions.

Hence the "fighting chance" in my title: we have started the switch to a carbon-free economy, but we have left it so late we may not avoid catastrophe.  We have a "fighting chance".

But I suspect the screws will tighten every year. Despite Donald Trump, Tony Abbott and other gibbering imbeciles on the right. What will it take to make the Republicans sensible about global warming? How many more hurricanes, heatwaves, floods? Miami constantly under water from "nuisance" or "sunny day" flooding?

The world is going to commit itself ever more urgently and with ever greater force to reducing CO2 emissions as the evidence of global warming becomes ever more obvious and the cost of de-carbonising continues to fall.  And that improves the odds of our "fighting chance".

Telsa to build world's largest battery bank in South Australia

Source

In this post, I talked about Elon Musk's amazing offer to build a battery bank in South Australia which would "solve SA's power woes".  Well, after a competitive tender, Tesla has announced that it will, in co-operation with the French alternative energy company Neoen, build the world's biggest battery bank in South Australia.  It's maximum output will be 100 MW, which is 3 times larger than any other battery bank, and it will store 129 MWh of electricity, which is 1.6 times the Aliso Canyon battery bank in California.

Musk said that a failure to deliver the project on time would cost the group $50 million, which suggests that this is roughly the cost, since Musk is sticking by his promise to build it in 100 days or it would be free.  It would provide 1/15th of South Australia's electricity demand for 80 minutes.  This doesn't sound like a lot, but it's not meant to provide power overnight, say, or for the afternoon peak.  It'll work a bit differently:

The hourly averages of wind power generation can be predicted with almost complete accuracy 24 hours out (and even a week out is a good indication)  - and the more wind you have the more accurate. Solar is even more predictable. What's difficult is the 5 to 15 minute prediction. Will we have 190 MW or 177 MW in exactly 15 minutes time? That is the trick. 

And that's exactly what a big battery allows you to plan for. What you do is smooth the gaps between generation and load. If that gap starts to grow toward 100 MW (the size of your battery) and you don't have anything else ready to go, THEN you start your diesel (gas) generator. And you turn it off as soon as a cheaper source comes [back] online.  [Hat tip to RobertAussie]

The battery bank will be used to prevent the kind of cascading failures that occurred last (southern hemisphere) summer in South Australia.  When a big generator or a power line goes down, it causes voltage and frequency on the grid to "jerk".  This can cause other generators or grid lines to "trip", which cause further failures potentially leading to a system-wide collapse.  Unlike other forms of storage (CSP, pumped hydro) or gas peaker plants, batteries can respond virtually instantaneously to fluctuations in the frequency or the voltage of the grid.  This makes a blackout like those which occurred last summer much less likely.

It's not big enough though to solve the problem of time-shifting.  Demand peaks in the late afternoon, when the sun is already past the meridian, and continues into the night when there is no sun.  And although wind supply is forecastable, it's not fixed.   To reach 100% renewables, SA will likely require 5 hours of storage, plus an additional interconnector via Broken Hill to the east coast NSW grid.  It seems very likely that South Australia will build a CSP plant near Port Augusta in the state's north (lots of sunshine there).  The Federal government has already agreed to to tip in $110 million to help fund it at a low interest rate as part of a deal to get the support of Nick Xenophon in the Senate.  And you may be sure that if this battery bank works as expected, there will be others: after all, at this cost, one hour's storage would be just $750 million.  But it is a beginning.  It emphasises yet again that at some point a 100% renewable electricity supply is feasible, and as the cost of renewables plunges, also inevitable.

Read more here:

Tesla to build world's biggest lithium ion battery in South Australia

Elon Musk's big battery brings reality crashing into a post-truth world

[Update: Here's an excellent info piece from RenewEconomy about the battery bank]

Pumped Hydro Storage

Source

Pumped hydro storage is the oldest form of electricity storage around.  It's been used for decades. How it works is simple.  When electricity demand is low (the wholesale electricity price  is low) water is pumped from a lower reservoir to an upper one.  When demand is high (wholesale price is high) water is released from the upper dam, flows down through the turbines, which generate electricity to produce power.  The price differential covers the cost of the pumped hydro facility.

I've talked about molten salt storage, battery storage, and molten silicon storage.  But I've more or less ignored pumped hydro before, because I confused it with conventional hydro, which requires large dams and strong river flows. The chart below shows the difference.

Source

One further chart is interesting.  It shows the potential for pumped hydro to make a profit based on .
the difference between peak and trough wholesale prices.  Notice how as storage hours rise, the incremental profit ("arbitrage") starts to decline., Up to 4 hours of electricity, profit rises, but from 6 hours to 10 hours there's no incremental improvement.

Source

I won't reproduce the whole presentation here.  Read it for yourself.  It's quite fascinating.  But also read this article, which makes a strong case for  pumped hydro on cost grounds.  The author says that 5 hours of pumped hydro storage would add just 25% to the cost of solar.

Pumped hydro is the perfect complement to renewables.  On the costing charts provided (slide 27 and 30), pumped hydro seems cheaper than batteries. But even if it's the same, it can play a part in our switch to renewables, because diversification isn't just good for supply, it's also good for storage.

An amazing offer

It all started when Lyndon Rive (head of Energy at Tesla) visited Melbourne to launch the new Powerwall 2 here: 

They are only starting to gain a foothold in the Australian market, but could batteries provide a near overnight solution to the energy woes that have hit South Australia and risk spreading east? 

At least one company believes so. In an elaborate launch in a former power substation in suburban Newport, in Melbourne's west, Tesla Inc said its technology could provide a fix within 100 days. 

The Californian company's energy products vice-president Lyndon Rive said it could install up to 300 megawatt hours of grid-scale battery storage in that time frame at a cost of about $66 million per 100 megawatt hours. 

"If you had storage deployed during the blackout [in] South Australia you wouldn't have had the blackout," Mr Rive said.

[From Melbourne's The Age newspaper.  Read more here]

This news then provoked a Twitter conversation between the Ozzie billionaire Mike Cannon-Brookes and Elon Musk:

To which Musk replied:

What Musk and Rive and Cannon-Brookes have done is to break the logjam caused by the hysterical (and dotty) opposition  to renewables of Oz's right-wing ruling coalition.  The LNP coalition has (for political reasons) been extremely critical of the Labor party regime in South Australia, and has (falsely) blamed several blackouts in the state on the high percentage of renewables in its energy mix.  There is an election in SA next year.  So the SA government would be very glad to make this relentless assault from the LNP go away. 

All of the solutions mooted up to now, by either side, have involved lots of money and big delays, plus steps backward to gas and (ugh!) "clean" coal.  So this proposal -- cheap and fast -- really breaks the gridlock.  Reaction has been predictable: euphoria and praise from almost everybody, grumbles and nay-saying from the fossil fuel shills and rusted-on LNP supporters. 

Musk is determined to cause a global transition to a carbon-free economy.  It would be wonderful publicity to be able to say Tesla solved South Australia's electricity problems.  Better still, there are probably still millions of Ozzies who have never heard of Tesla cars, let alone Tesla batteries, and now suddenly Tesla is on the main pages of our newspapers and on TV.  So Tesla  wins.  But,  so does South Australia.  And so does the world, because this will conclusively show that it is possible to transition to a carbon-free economy, and that the variability of renewables can be dealt with, cheaply and efficiently.  It's a win-win for everybody except the coal dinosaurs.

What was really interesting is that Musk said the cost for one kWh of storage was now just US$250 for 100 MWh+ systems.  He means the capital cost, not the cost per kWh of output.  He's effectively more than halved the cost of storage utility-scale storage.  Again.  I said when I looked at the price declines announced for the home storage unit, the Powerwall 2, that a similar cost decline in wholesale storage hadn't been announced.  Well here it is, announced on Twitter no less.

Assuming each battery is discharged once a day, and lasts 10 years (though there should still be plenty of juice even after 15 years) I work out the cost per kWh of usage as 250/365/10 = US 6.8 cents, or US$68/MWh.  That doesn't mean you add $68/MWh to the cost per MWh of wind or solar.  You add 1/24th of that for each hour of storage.  So wind with 6 hours of storage goes from, say,$30- $40/MWh to $47 - $57/MWh.  Still far cheaper than coal.

The advantage of batteries is that they don't just store power.  They can provide grid stability.  Their extremely rapid response, within micro-seconds, is good for short term stabilisation of the grid, when for example, a major generator or a major power line goes down, and voltage and frequency "jerk". 

Daily SA electricity demand is 35.4 GWh. So one hour's demand would be 1.5 GWh, and battery storage for that one hour would cost US$375 million.   That works out at just $220 per inhabitant of South Australia.  Prolly, though, the power would be supplied by a PPA (power purchase agreement) or a reverse auction which would mean no capital outlay by the government.

My rule of thumb would be that for each 10% of renewables penetration in the grid we will need one hour of storage.  As we get to closer to 100% we will need 2 or more hours for each 10%, and to get from 80 to 100% we will likely also need long-term or seasonal storage.  The CSIRO has calculated that with a 100% renewables grid, 12 hours of storage would be needed, and the Australian National University thinks 18 hours would be enough.  South Australia has 45% renewables penetration, so it would need 5 hours of storage , but one hour would do very nicely to start with while the state builds another interconnector (with NSW this time) and also adds other forms of storage including pumped hydro and CSP.

I can't emphasise enough just what a game changer this is.  As RenewEconomy says:

Tesla founder and CEO Elon Musk has long predicted the imminent end of the fossil fuel era. But it took a couple of tweets between him and another billionaire, Australia’s Mike Cannon-Brookes, on Friday to highlight just how close this is. 

Australia’s fossil fuel “elite” – the industry, the politicians, the regulators and the media – have been kidding themselves that new battery storage technologies are “decades” away from being competitive with coal and gas. 

It’s what Australia’s energy ministers were told by the Australian Energy Market Operator at a COAG meeting last year, and US energy giant AES was stunned to find the same levels of ignorance when it spoke to ministers and regulators as recently as last November. 

As we reported last Thursday, Tesla announced that the inflection point wasn’t 20 years away. It was 100 days away. That, at least, was the time it would take to build a 100MW battery storage facility in South Australia, once planning approval and a contract had been signed.

As they say, now we're cooking with gas.