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Is Thermal Power Electricity decreasing at last?

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Jose A. Martinez's picture
CEO ADEX

CEO of a CleanTech company, specialized in making thermal power plants more flexible, efficient and sustainably. Partner of a VC for disruptive SMEs and Business Expert of the UE. Business Angel...

  • Member since 2020
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  • Oct 2, 2020
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Since 1992 when United Nations created their Framework Convention on Climate Change, a list of annual conferences has been held to try to agree on a reduction of the use of Thermal Power, in order to decrease the CO2 emissions into the atmosphere.

According to international agreements, the most famous are the ones held in Kyoto (1997), Copenhagen (2009) and Paris (2015).

However, there is a huge gap between those agreements and the reality, for very different reasons. Please, have a look at the dynamic graph below where you can see how the Electricity produced from Thermal Power sources has evolved between 1985 and 2018 per region:

Flourish logoA Flourish bar chart race

Part of the coal-fired power plants and oil power plants are indeed being shut down. However, only a small part of their electricity is substituted by carbon-free energy sources. The rest is provided by more gas power plants, which offer more flexibility and emit less CO2. The majority of the new renewable capacity is covering the constant increase in total demand.

And there are many opinions and forecasts about how the future will be. One of the best supported is the analysis done by International Energy Agency at their IEA World Energy Outlook 2019:

Global Electricity production (TWh) by source. Forecast includes new Climate Change Policies

The share of Thermal Power in the mix will decrease from 64% to 49%, which looks good. Nevertheless, as the total generation is expected to grow from 26,600 TWh up to 40,700 TWh per year, the total fossil electricity will grow in TWh on 17%.

This increase will impact international commitments to reduce CO2 in the atmosphere. There are mainly 3 factors that drive this situation:

  1. A steady increase in Electricity demand, both per country and on a global basis
  2. The required investment on renewables to get rid of Thermal Power Plants is huge and we need too much time to fund it
  3. Lack of flexibility of Thermal Power Plants, which forces curtailment of renewables and limit their integration in the mix

COVID has impacted in electricity demand and showed growth in demand may be reduced. But this is hopefully a temporary situation. Whenever heavy industry comes back, we will likely recover the figures of the past.

Money is limited and the balance between profitability and social impact constrains investment. And some big subsidizing programs will end during these years (e.g. Germany or the USA).

So the most cost-effective action and with an immediate effect is increasing the flexibility of thermal power plants. They are going to coexist with renewables for many years so we must change our minds. They are seen as the devil and so any investment on them is not well considered. But, either if you like it or not, such investment will help us to decrease expected CO2 emissions.

A great tool to increase the share of renewables is, surprisingly, investing in thermal power plants!

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Matt Chester's picture
Matt Chester on Oct 2, 2020

Love the dynamic graphic Jose-- would love to see one of those that shows the year by year evolution of the portion of the energy mix side by side with it. 

Roger Arnold's picture
Roger Arnold on Oct 3, 2020

Does lack of flexibility in thermal power plants actually lead to curtailment of renewable resources? My understanding is that under the "merit order for economical dispatch" renewables, with their zero marginal cost of production, will always underbid production from thermal plants. Renewables would be curtailed only when all available demand is already being served by other renewables.

I realize that "merit order for economical dispatch" is only a way to manage transactions on the wholesale power market in nominally "deregulated" utility regions. I also recognize that FERC rules are complex, and that it's possible to have substantial power being supplied to the grid for extended periods under contracts that shield the supplier from arbitrary curtailment. I assume -- though it's only an assumption -- that that's how most nuclear power is supplied. In that case, the "available demand" for renewables to serve would be less than it would otherwise be. Curtailment of renewables could occur even when substantial production from thermal plants was ongoing.

If that's the case, can calls for "enhanced flexibility" from thermal power plants be understood as primarily a call for renewables to have the right to force curtailment of baseload supplies? 

That's maybe a trick question, as I know that flexibility does have benefits that go beyond expanding the demand available to renewables. But AFAIK, the benefits have to do with reducing the need for fast-response peaker units and for separately contracted ancillary services. Those are much the same as the benefits that can be provided by modest amounts of grid-level battery storage.

Jose A. Martinez's picture
Jose A. Martinez on Oct 3, 2020

Roger, your assumptiom about a lower "available demand" is totally correct, unfortunately. Curtailment of renewables mostly happens when thermal power plants are supplying electricity but they cannot reduce their minimum load or increase their ramping rates. And this is the real problem. Unless, thermal power plants leave room for renewables (so they are more flexible) it would take much longer any energy transition plan.

I enclose an image from CAISO, which publish openly their curtailment

CAISO renewable curtailment on 26th of March of 2020

CAISO Renewable curtailment in BLACK  on 26th of March 2020

The black area is the Renewable electricity which could have been produced but had to be curtailed because Thermal Power Plants were unable to produce less.. During that day 22 GWh were curtailed !!

On annual basis, CAISO curtails 8-10% of renewable electricity.

If thermal plants were as flexible as required, all those CO2 tons would have been avoided.

I hope you agree that investing in thermal power plants flexibility is the first action to increase renewables.

 

Roger Arnold's picture
Roger Arnold on Oct 3, 2020

Thanks for the response, Jose. I'm afraid I can't give you a simple answer as to how I feel about investing in flexibility in thermal power plants. "It depends."

I've no committment to renewables, per se, and especially not to variable renewables. I've a strong committment to sustainability, but right now my first priorities must be to curtailing carbon emissions, and doing so quickly enough to hold off some of the worst effects of global warming and rapid climate change. Renewables are a tool for helping to curtail carbon emissions, but they're not the only tool and maybe not the best.

Assuming that increasing renewable's share of generation while keeping curtailmant to a minimum is held as a desireable goal, then investing in flexibility in thermal power plants is a tool for accomplishing that. But once again, it's not the only tool and maybe not the best. Other tools include energy storage and demand resonse -- both of which encompass a wide range of particular approaches. 

Part of my hesitation to endorse investment in flexible thermal power plants is that, at least as I understand it, it involves replacing existing fossil fueled capacity with new -- and likely more expensive -- fossil fueled capacity. If demand for electricity were growing at such a rate that building new fossil fueled plants were a necessity, then flexibility would certainly be a priority. But for replacement of existing capacity rather then new capacity, the case is less clear.

Of course, we're speaking here in generalities, without nailing down the key questions of "investment by whom" and "in what regulatory context?". Say we were addressing the management of a fossil fueled electricity supplier, and telling them that they should upgrade their generation capacity for more flexibility so that they can dial back what they supply in favor of a competing supplier of renewable energy. I suspect that pitch would not be well received.

Bob Meinetz's picture
Bob Meinetz on Oct 4, 2020

"Say we were addressing the management of a fossil fueled electricity supplier, and telling them that they should upgrade their generation capacity for more flexibility so that they can dial back what they supply in favor of a competing supplier of renewable energy. I suspect that pitch would not be well received."

Roger, your circumspection assigned all due credit - fossil fuel interests have never willingly dialed back an opportunity for profit - ever - and with the average longevity of a natural gas plant estimated at 47 years, the idea they would start in 2030, or 2040, is a luxurious fantasy humanity can't afford now. Much less, in 2067.

Last week I was invited to participate in a ZOOM meeting with former Secretary of State John Kerry, whose passion for addressing climate change might surpass that of Al Gore. During the meeting he revealed military / Homeland Security sources estimate minimum global temperatures by 2100 to be +4°C - twice IPCC estimates.

Should U.S. estimates prove accurate, global impacts will be cataclysmic. Multi-meter sea level rise will put New York, New Orleans, London, Tokyo, Rio de Janeiro, Buenos Aires, Hong Kong, and countless other coastal cities under water; equatorial maximum temperatures of  >140°F would be the "new normal" - if anything could be considered normal anymore.

There is no longer one second to waste on misplaced optimism.

Dr. Amal Khashab's picture
Dr. Amal Khashab on Oct 4, 2020

 I believe that investing in thermal power plants flexibility has a wide spectrum of actions. Some of them may be innovations , which need time . It might means energy storage facilities as well as expansion use of open cycle gas turbines as peaking units. Every option could be  unique for a specific grid once feasibility assessment has been accomplished.

Roger Arnold's picture
Roger Arnold on Oct 4, 2020

I've previously understood thermal plant flexibility and energy storage to be competing approaches to accommodation of variable renewables on the grid. But you're right; in particular situations, modest amounts of energy storage might be employed within a thermal power plant to support (more) flexible operation.

My previous understanding of flexibility in thermal power plant operation -- and a factor in my hesitation to endorse it -- was based on where I first encountered the term. It was associated with Germany's Energiewende. When the Germany's Greens pursuaded the government to close down nuclear power generation, several new coal-fired power plants were built to replace some of the lost capacity. The new plants were touted for their flexibility. They could ramp frequently and relatively quickly, and they had broad and relatively flat power bands over which they could be throttled without undue loss of thermal efficiency. That made them good "partners" for variable renewables. They expanded the share of the generation market available to renewables before they bumped up against curtailment.

A dirty little secret of big wind and solar is that once the need for curtailment arises, operation of wind and solar farms becomes unprofitable. It's not just loss of revenue to the units curtailed; the wholesale power market price falls to the marginal cost of production. That's zero for solar and negative for wind where production tax credits apply. So even if curtailed generation is very small relative to total generation on the grid, it has a disproportionate impact to the bottom lines for VR producers. They have strong monetary incentive to oppose baseline and favor "flexible" generation. Even when the baseline generation is carbon-free nuclear.

Roger Arnold's picture
Roger Arnold on Oct 4, 2020

I've been reviewing the website for ADEX, the CleanTech company that Mr. Martinez heads. I find I owe him an appology for a misunderstanding on my part. I wrote:

Part of my hesitation to endorse investment in flexible thermal power plants is that, at least as I understand it, it involves replacing existing fossil fueled capacity with new -- and likely more expensive -- fossil fueled capacity. <..>

Well, that was how I understood it, and in many cases that's what it might indeed involve. If you go shopping for gas or steam power turbines, you'll find new models specifically marketed for flexibility. They have mechanical design features and fabrication methods that allow for fast ramping without undue "wear and tear", along with features that support a wider, flatter power band for efficient throttling. But evidently, upgrading to a whole new turbine system isn't the only way to improve flexibility.

The approach that ADEX markets is modest. It's an upgrade to the power plant's control system that uses predictive models to compute optimal time-value trajectories for various control parameters. The result is said to be smoother, more efficient, and less mechanically stressful ramping.

I'm a little surprised that the approach ADEX markets isn't already standard practice. I wouldn't expect to find much room for improvement in the control algorithms for a mature technology like thermal power generation. But I've been surprised before, when I've had ocassion to dig in to particular systems, by how naive the control algorithms turned out to be. So the assertion that there is indeed considerable room for improvement in control of thermal power plants, while surprising, is not incredible. It's certainly worth checking out.

Jose A. Martinez's picture
Jose A. Martinez on Oct 5, 2020

No apologies required, Roger. Glad to be more aligned now.

As I finished my post,

A great tool to increase the share of renewables is, surprisingly, investing in thermal power plants!

Paul Cleri's picture
Paul Cleri on Oct 6, 2020

Great graphics, especially the moving bar chart.  Would be good to see more data presented in this manner.

Jose A. Martinez's picture
Jose A. Martinez on Oct 7, 2020

Thanks Paul.

I will include it in my next post too.

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