In a recent column, solar advocate Paul Wolff proposes a solution to the "variability" problem with Solar PV: “The truth is that Georgia’s wealth of solar and offshore wind capacity, supplemented by natural gas, is our best option. Unlike nuclear or coal plants, which are cumbersome and expensive to power up and down to meet variable demand, natural gas can be turned on and off virtually at the flip of a switch to offset periods when the sun and wind don’t provide enough power.”
Wolff thus would construct a hybrid power system, with a natural gas turbine system to provide the base load power and thus fill in the gaps left by variable (green, as in solar) power.
Just one question: Where's the beef? 9/27/12 Update: Here's a NYT article on new gas plant technology that goes to this issue.
I’m requesting solid, dollar-and-cents evidence to support this “hybrid” brown/green power plant proposal. My own experience convinces me he’s got none. I hope I’m wrong. Some background: I installed a 10KW, grid-tied, Solar Photovoltaic (PV) system in Gillis Springs, GA., for $3.5/watt up-front price ($1.4/watt tax-credited subsidized price). It's featured here.
I've also written about the economics and politics behind grid-tied, individually owned, PV systems.
Part of my research involved interviewing current and retired power company executives. The prime obstacle to PV, and the reason why power companies don't want it, is variability: Customers want their A-C to work all night, and their alarm clocks to go off at the right time. Coal and nuclear powered plants (brown power) produce a steady, “base-load” of power. Green (PV, wind, etc.) does not. Green (PV, specifically) at best supplies primarily “peak-load” power (sunny days when demands peaks) but remains too variable (cloudy days) and thus is worth less to electric power companies (would you buy a reliable or unreliable car?).
So, utilities want brown, not green power. But greenies got legislation passed forcing utilities to buy green anyway, and that’s the only reason why my utility buys my PV-generated electricity (I have negative-$100/month power "bills"). You can see how Georgia’s legislation works in my open letter to my utility.
Paul Wolff's solution here is fetching: Create a hybrid system. He would “light-switch-flick” a gas-turbine powered plant off and on throughout the day and night as PV, wind, and any other 100%-variable alt-energy sources kick on and off. The turbine would fill in the gaps left by the variable sources. This hybrid system would thus produce a continuous flow of electricity. More sun and more wind would result in less gas (a brown fuel) consumption. Stretched out over a large area and smart-grid coordinated, less and less gas (brown) power would be needed (stretched out PV would be especially useful because as clouds descend over one area of PV arrays, sun would shine over another; the same process could be envisioned for wind turbines).
If only it was that easy. So I ask you, Paul, to contact me (I live in Southbridge) and share with me the evidence -- the facts -- supporting your claim: firstname.lastname@example.org. And I want dollars and cents facts, please, not greenie-fantasizing.
Because I’ve designed a new “Habitat-for-Humanity,” self-sufficient living building model (see above) that is a POSITIVE-energy home for $87.50/sq.ft. Plus, I am offering, free of charge, assistance to those who wish to “go solar” -- but only if they commit to erect 10KW for no more than $1/watt (overpaying greenies simply hurt the green-power movement by blithely supporting high prices and enabling Solar Corporate Welfare Queens, who in turn raise their PV prices to cop the free-money (subsidies) spread).
To that end, my above-noted, free “web-book” advocates tens of millions of individual 10KW array owners reaping $100/month in “meter gold,” as I do (basically a 10-year payback on a 30-year system). That’s net, new wealth, not “government-printed” wealth, and reaped/controlled by millions of Joe Six Packs, and not Big Power, nor Big Government. And they'll do it in a decentralized (thus, not terrorist-targetable) electrical power system.
But that only makes sense if all that newly generated power (80% of my array’s power goes into the grid, I only use 20% for myself) efficiently and usefully feeds a grid smart to use it. And that also only makes sense if PV and wind can be built to produce power at grid-parity (i.e., same or less cost to produce as coal, nuclear, or gas) cost: $1/watt, many say.
Paul says it can be done, using the hybrid base/variable load system as he envisions.
Yet, I fear he’s simply imagined it and convinced himself that it’s “cost-feasibly true,” when in fact it’s not. And if it is true, then why aren’t utilities scrambling to do it? OK fine, it’s all a brown-power conspiracy (the stock greenie answer). I invite anyone with evidence (I'm an attorney) to contact me and we’ll both present it to the Justice Department and demand an investigation analogous to this.
I certainly want Paul’s claims to be true. At $1/watt, I project that Joe Six Pack will buy and install his own (I did!) 10KW array from, ultimately, “Solar Aisle” at Home Depot and Lowes. Especially if PV becomes, as some project, “plug-and-play simple,” then that “meter gold” will be a no-brainer to “Joe,” who will scramble to catch those metaphorical sun-gold coins falling out of his meter. Plus, like me, he'll never pay another power bill for 30 years, thereby enhancing his home’s resale value.
But it's a numbers game -- how much will the local utility pay him for his excess power? My 10-year payback cycle contemplates a $10K installed cost for a 10KW system, plus a 7 cents/KWH, "avoided cost" payment from the local utility for excess power fed back into the local grid.
Yet, that’s only half the equation. Joe’s excess power has to be fed into a utility grid that can effectively (cost-feasibly) use it. Ignoring economics and simply forcing utilities by government fiat (Renewable Portfolio Standards and other forms of unfunded mandates that stealth-tax ratepayers) is not the way to go, as it only engenders subsidy-mongering, wasteful construction.
I'm betting that the local utilities connected to those "subsidy farms," if they could speak freely and truthfully, would tell us that they need a critical mass of variable sources, so that each variable source (when it peters out) can compensate for each others variability. Sporadically located "subsidy farms" like these don't fit that bill. Plus the local grid must be much smarter to handle all that load-surging and dropping, so why build such farms in the first place if there's no cost-feasible way to capture their yield? (Hint: they would never have been built without subsidies, which is simply another way of forcing us all to pay for them -- even if they make no economic sense and benefit the few at the expense of the many).
Hence, the actual, unsubsidized cost of Paul's proposed hybrid arrangement and necessary smart grid costs must be added up to see if his proposal makes any economic sense. I don’t see how it does (recall that T. Boone Pickens wanted to harness Midwestern wind power only if the tax/ratepayers first absorbed the astronomical grid-facilitation costs -- and what happened to his plan?).
Paul claims that it does make economic sense. I ask him for his evidence. I ask this question again, here. More on this topic here.
Here's another hybrid (but no cost data, which I find irritating).
Ditto for this geothermal hybrid. A friend writes about that: "One of the smart strategies with large solar plants is to co-locate them with existing power plants - generally natural gas. That way you can piggyback on some of the existing infrastructure such as power-lines, security, operators etc. Now we know solar + geothermal works too." My question, though, is this: I'm interested in the execution -- can, for example, gas turbines be tuned fine enough to stop when Solar PV electricity flow starts? Or, is there substantial -- and wasted -- overlap of some sort?
July, 2012 update on that geothermal hybrid plant here. And yes, of course it is being subsidized: "The DOE also has another reason for touting the project. The Stillwater plant received $40 million from the federal government's American Recovery and Reinvestment Act -- the same program that was put through the wringer last year following the Solyndra debacle. After receiving a $535 million loan guarantee through the Recovery Act in 2009, Fremont, California-based Solyndra filed for bankruptcy two years later."
Since we are co-investors in it, the government should require timely release of independently audited cost-data to evaluate whether it makes any economic sense. I sure hope it does.