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Renewables Accelerating

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This paper is primarily on U.S. photovoltaic (PV) and PV plus battery energy storage systems (BESS). Section 2 is on recent news on wind, PV and PV+BESS economics, and specifically how their levelized cost of energy compares with other types of generation. Section 3 is on recent major PV+BESS and PV-only projects. It also includes some amazingly low power purchase agreement energy-pricing.

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John Benson's picture

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Bob Meinetz's picture
Bob Meinetz on Jan 29, 2020 4:19 pm GMT

John, in your paper you continually refer to "PV+BESS", as though the batteries near Eland and other solar farms will only be storing clean electricity.

But electrical energy does not move through AC transmission in only one direction. The batteries at Eland are entirely capable of storing electricity from the grid as well - in fact, economics and capacity factor dictate 70% or more of the electricity stored in Eland's batteries will be a grid mix. With gas-fired generation making up one-third of CAISO's electricity, it remains to be shown Eland will offer any reduction in carbon emissions at all; that the farm is not increasing emissions by storing energy generated by gas plants and wasting 15-20% of it in resistance and other losses. It remains to be shown PV+BESS has a significantly smaller carbon footprint than PV+COAL.

You might try to contact 8Minute Energy and ask whether electrical energy stored in Eland's batteries will be exclusively solar in origin, and they might return your call (I'll save you the bother - I've tried, and they don't).

Joe Deely's picture
Joe Deely on Jan 28, 2020 7:59 pm GMT

With gas-fired generation making up one-third of CAISO's electricity,

Of course this doesn't really make sense - since a lot of NG generation on CAISO grid occurs when the sun isn't shining. NG usage is lower during the prime charging period.

Even on a Monday in Jan-2020 NG usage is 20-25% during the "charging period" between 10am-2pm.

Note the rise in NG usage after 5pm - the time when batteries that John is describing would be discharging - thereby replacing some NG generation.

Of course, this chart is Jan 2020.  With plenty of new solar projects lined up - what will this chart look like in Jan 2025? 

Already in spring of 2019 - NG generation was below 10% during the prime charging period. What will Spring of 2025 look like?

"Skate to where the puck is going"


Bob Meinetz's picture
Bob Meinetz on Jan 29, 2020 4:12 pm GMT

Joe, there is no "prime charging period," or a time when batteries "would be discharging." It could be any time, and depends on what other resources are available, the weather, day of week. On cloudy days or before evening peak it will be mostly gas-fired electricity being stored - or did you think the solar farm owner was only going to charge his expensive batteries with 100% pure sunshine?

Joe Deely's picture
Joe Deely on Jan 30, 2020 5:09 pm GMT

Bob - you can believe whatever you want..

In the real word...batteries will be charged when electricity is cheap and discharged when prices for electricity is higher.... simple economics.

Note the chart below is a few years old... that dip during midday keeps getting lower.

Lili Francklyn's picture
Lili Francklyn on Jan 29, 2020 11:17 pm GMT

Bob, I believe California has implemented a strategy to prevent batteries from charging from grid power, that is a condition for getting Net Metering payments for storage. It does in fact prevent power from moving in both directions. You can learn more about it here: These types of strategies are also important in states like MA which have new "Clean Peak" storage laws.  

Matt Chester's picture
Matt Chester on Jan 30, 2020 1:02 pm GMT

really interesting-- thanks for the additional resource, Lili

Matt Chester's picture
Matt Chester on Jan 28, 2020 5:18 pm GMT

Great summary, and I appreciated seeing the case studies of projects across the country John.

When it comes to costs of solar+storage, do you foresee future direct impacts from regulators tipping the scale one way or the other-- such as carbon pricing making solar more competitive or some sort of framework that would pay gas/nuclear/etc. for the ability to provide baseload non-intermittent generation?

Joe Deely's picture
Joe Deely on Jan 28, 2020 7:47 pm GMT

Definitely accelerating... I am tracking over 8GW of wind/solar in the Western US (AZ, CA,CO,ID,MT,NM,NV,OR,UT,WA,WY) which are due to go-live in 2020.


2021 is gonna be a very tough year for coal out West. 

Bob Meinetz's picture
Bob Meinetz on Jan 29, 2020 4:11 pm GMT

I noticed you're still not tracking gas consumption, Joe, so you probably weren't aware 4.8 GW of gas that was supposed to be replaced by renewable pixie dust has been extended - and that's just in California.

2021 is gonna be a terrific year for methane! Definitely accelerating.

Joe Deely's picture
Joe Deely on Jan 30, 2020 5:34 pm GMT

Of course I track CA NG capacity - here is an updated version of chart which I have put up on this site before.  Data is thru Nov 2019 - I'll put out an update once Dec data comes out next month.

6.7 GW of NG capacity retire in last 6 years.

I agree with the pause in retiring all of plants you mention in your link. Too much NG being closed too fast. Majority of battery installations will not be installed till 2022. 

Surprisingly, the CPUC did approve the closure of the Inland Empire NG plant - 850 MW - that will show as closed in February.

The California Energy Commission on Dec. 11 approved the premature decommissioning and demolition of General Electric Co.'s 10-year-old, financially struggling natural gas-fired Inland Empire Energy Center, a more than $500 million generating facility in Riverside County once heralded as the future of the global power sector.

The facility will cease power production at the end of 2019 and begin a 12-month decommissioning and demolition process, according to the plan.

Like the Moss Landing plant it looks like a large battery installation will be implemented at this location.

In its next incarnation, the Inland Empire site could be reborn as a large-scale battery system better designed to meet the state's peak power needs. A company called Nova Power LLC agreed to purchase the project site to transform it into a large-scale energy storage facility.

That would make Inland Empire one of numerous gas-fired power plants in California being directly or indirectly replaced by battery storage systems to serve peak power demand.

Great idea for all of these retiring plant locations - use the infrastructure already there to install cheap storage.


John Benson's picture
John Benson on Jan 29, 2020 10:32 pm GMT

Thanks for the comments, Bob, Joe and Matt:

Electricity goes where it wants to. As far as what a given generator in California is used for, this mainly has to do with financial accounting as performed by CAISO. (who buys the electricity and who sells it). If a load-entity buys electricity from generating-entity under a power purchase agreement, as far as CAISO is concerned, this fulfills long-term purchasing (resource adequacy) requirement. In the short term (day ahead and day of a transaction) CAISO is more concerned with maintaining grid stability. There is a simplified diagram of this process in section 2 of the first paper linked below, and the rest of the paper goes into more details. The second link below is to a paper which describes the California resource adequacy procedures:



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