Tdworld 2911 Renewable2

Is California Able to Handle 100% Renewables?

May 11, 2015
Not really, certainly not now. And cavalier pronouncements won’t make it so.

“We could get to 100 percent renewables,” Michael Picker, president of the California Public Utilities Commission,  said at the Bloomberg New Energy Finance summit in New York on April 7. “Getting to 50 percent is not really a challenge.”  

Not a challenge? Really? That’s a remarkable statement considering the struggles California has had with the existing penetration of renewables. Remember the famous “Duck Curve” showing the imbalance of generation and load over a 24 hour period? Here’s a  primer put out by the California independent system operator (CAISO) in 2013. Also check out: Solar Will Shine Brighter With Smarter Inverters.

The problem at hand is too much solar coming on too fast at the wrong time. CAISO is scrambling to develop ramping protocols for conventional generation and utilities are working with regulators to allow some control of inverters so they can reduce the uncontrolled increased bumping of the grid when the sun starts and stops shining.

The Bloomberg article goes on quoting Picker:

“... the grid already is comfortably managing solar and wind energy that reached as much as 40 percent of the total a few days last year. In the years ahead, authorities can add the flexibility needed to manage power that flows only when the wind blows or the sun shines.”

It doesn’t sound to me like the engineers and other folks down in the trenches are all that ‘comfortable” – at least the ones I’ve talked to aren’t.

I’m all for pushing the envelope and California has certainly done that. See California Breaks Solar Record: Admit it - We Need These Folks. But I’ve also been one of the technical folks in the trenches who helped clean up the little messes left by thoughtless regulation, air-head legislation and cavalier statements to the media.

Again the Bloomberg article goes on:

“We actually have the technical problem of too damn much electricity on occasion,” Picker said. “We’ve had to curtail renewables on top of curtailing just about everything else except for the nukes.”

Well, you see Mr. Picker, that’s the problem – too much at the wrong time, too little at the right time. That’s what makes system operators ‘uncomfortable’.

Here are a few comments from our expert panel:

Matthew C. Cordaro, PhD

The suggestions embodied in the comments made by Michael Picker, president of the CPUC, are out of touch with reality. Reliably providing a significant fraction of a region's electricity with renewable sources requires substantial support from fossil and nuclear units, as well as storage devices, all backed up by a strong grid structure. This is very costly and cannot be trivialized by broad statements based more than anything else on policy dictates and a warm fuzzy philosophy that the details will take care of themselves.

As a former grid manager, I have to say that the complexity and cost of what is being proposed in California is intimidating and appropriately characterized by the old adage, the devil is in the details. Alas, we should not forget what happened in the state around the turn of the century when much of the same reasoning was applied to the deregulation and restructuring of the utility industry. Then and now, rotating statewide blackouts produce no benefits for California, just pain and hardship.

Virgil Rose

Michael Picker, President of the California Public Utilities Commission, recently said “California’s power grid could handle taking 100 percent of its supply from renewables such as wind and solar, and meeting the goal for half that amount will be no problem; authorities can add the flexibility needed to manage power that flows only when the wind blows or the sun shines.”

Of course anything is technically feasible through the intelligent application of grid control technologies and reinforcing the utility electric infrastructure. The challenges that will need to be addressed are: supply and demand location and time dependence.  Of course the more closely one can match resource and load in time and location, the more efficient the grid will operate. Although possible, any complete solution probably would not be cost effective, without market pricing reflecting the true cost of service. 

Storage solutions have long been the desired solution for modulating the timing of resource and load swings.  Adequate and cost effective storage technologies are still in our future but the timing of the necessary economic breakthroughs is still uncertain; and storage may not be able to completely address location constraints.

If we take a customer perspective of the situation for addressing one aspect of the challenge, the utility could provide a unique rate structure for each customer (or group of customers) based on the timing and location of their service with respect to location and timing constraints.  This may be politically challenging for the long run, but it would provide the right market signals to both resource and demand utility customers. With these signals, resource deployment and demand side management could be optimized over time.  This is not unlike real-time pricing approaches on the transmission grid.

If we assume the regulator would never adopt such a system because of the rate payer and resource provider political pressures, the regulator might adopt a ‘shadow price” concept.  The idea is each customer’s bill for consumption would have two items.  One being the current bill (current rate structure) and a second being a “shadow price” which would be the true cost of service for their time and location.  The shadow price could be interpreted as the long term price target for the demand customer and provide a realistic value of a resource addition to a potential generator or grid solution provider. Such “shadow pricing” would also provide feedback to regulators as they struggle with policy decisions designed to achieve renewable goals for broader societal objectives.  

Todd "Ike" Kiefer

Fantastic pronouncements like those from Michael Picker and Amory Lovins and Jacobson & Delucchi need to be held up to reality every once in a while.  It is just a bit ironic that the CPUC president’s comments to Bloomberg should pop into the headlines on the same day as this story about how California is coping with huge wind and hydro power shortages by buying fossil fuel generation .  

If one truly believes the climate is changeable, it is the height of idiocy to then advocate for powering all of civilization from climate-dependent energy sources.  Bloomberg and Scientific American need to be smarter than to lap this stuff up and regurgitate to their subscribers uncritically. 

Wind and solar have increased the reserve margins necessary to insure a stable grid, and that burden is primarily borne by dispatchable fossil fuel generation.  Were we to reach Picker’s 100% intermittent RE penetration in capacity, we would still need at least 75% of full capacity operational in dispatchable fossil fuel and nuclear to cover RE’s capacity factor gap.  Were we to get to 400% intermittent RE penetration, we would still need that 75% available on standby to cover the stochastic dips in production when there are widespread and prolonged weather events.  Blackouts are not an option for our cyborg civilization where everything is urbanized, mechanized, and digitized. 

There is apparently no limit to what we can spend on bad ideas and what we can ask the ratepayers and taxpayers to pay for implementing them.   We can work diligently making the grid less stable with gobs of RE, while working equally diligently trying to offset that instability with new natural gas generation and new demand-side technology that shifts the burdens to fossil fuels and to the consumer who used to be assured of on-demand power without paying a premium.  We have been doing quite a number on the ratepayers with this churn by raising their rates faster than inflation nationwide since 2005, despite a massive recession that crushed load growth and any legitimate need for new most of the new generation and transmission built since then.  We should not give ourselves credit for solving problems of our own making, especially at others’ expense.

RE is more burden than blessing until it is made dispatchable in a cost-effective and self-contained way such that it can successfully compete on the day-ahead market for firm blocks of power without subsidy or mandate.  Unfortunately for Picker and California, energy storage technology is still an order of magnitude from the necessary performance metrics and is stubbornly refusing to evolve according to Moore’s Law.

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