This post looks at the message promoted by the gas industry that natural gas is the necessary complement to renewables such as solar and wind, because the latter are variable and thus need a backup power source that can quickly be brought on line. There are other and perhaps even better ways of addressing variability that also need looking at.
We have been barraged lately with claims from the natural gas industry, from gas turbine manufacturers and fossil fuel apologists, that the “nice” fossil fuel is really a good complement to variable wind and solar energy.
As I have made clear in previous posts (i.e. Is Natural Gas a Good Guy?), I am in favor of natural gas (NG) electricity generation, and consider it both likely and appropriate that the US is going to build more NG generation over the coming decade than any other form of generating capacity. Hydraulic “fracking” of shale gas has some immediate challenges in the form of methane leaks and apparent groundwater contamination by certain rogue drillers — but most likely these will be overcome, and aside from these concerns, NG has a lot going for it: it is cheap, plentiful, domestic, and less-polluting than other fossil fuels.
However, what shall we make of GE’s claims this week that “By rapidly ramping up and down in response to fluctuations in wind and solar power, the technology will enable integration of more renewable resources into the power grid”?
It certainly sounds good — this nice, clean fossil fuel will help us wean ourselves from dirty coal and act as a “bridge” to our renewable energy future.
Christopher Mims was also active this week, talking about the virtues of NG on Alt Energy Stocks. Mims quotes an expert, Dr. Paulina Jaramillo, a professor of engineering at Carnegie Mellon:
“I would say that without natural gas, the grid will not be able to manage the variability and intermittency in power output from wind and solar plants.”
Now as a wind energy enthusiast, I am very happy that credible people like GE and Christopher Mims (former editor of Scientific American) are assuming that everyone will want to build more wind capacity. But does wind energy really need NG — or is this just marketing spin to sell more gas turbines?
I am suspicious.
The first thing that catches one’s eye is that GE plans to offer its new gas turbine to the European market in 2014, and has no plans to offer this machine in the US, where gas is actually cheap. Natural gas is, in fact, not very cheap or plentiful in Europe, yet “Chief Executive Jeff Immelt, speaking last week at a conference in Florida, made clear that GE is bullish on the outlook for natural gas as an energy source, calling it cheap and plentiful.”
So, Immelt is in Florida, talking up his turbine’s selling points for the US market, but actually making it and selling it solely in Europe.
Hmmm… it seems like we’re getting some marketing spin there.
As for Mims’ article, the expert he quoted does not address the immediate issue for wind grid integration in the United States. This is the issue that grid operators and policy-makers do not like to admit, namely that grid operators in the US can integrate a lot more renewable energy capacity just by planning better and introducing markets.
From the article: “As executive director of the RenewElec project, which aims to increase the proportion of intermittent sources of renewable energy in the world grid, Jaramillo specializes in thinking about the transition off fossil fuels. She doesn’t believe we’ll be able to get more solar and wind on the grid without natural gas, precisely because the only alternative — storage mechanisms like batteries and demand-side management — aren’t far enough along.”
“The only alternative,” she says.
Dr. Jaramillo would have us believe that grid operators (people who run the grid like ERCOT, California ISO and NY ISO, not generating companies like MidAmerican, ConEd, and PG&E) are already doing all they can. So, they have to turn to the “only alternative” left, which is new forms of flexibility like demand response and storage.
This is blatantly untrue. In fact, about one third of the nation (mostly in the Northwest and Southeast) has no electricity markets at all. So there is no way to trade energy. To make matters worse, many balancing areas are far too small (there are over 130 balancing areas in North America — a “balancing area” is the territory over which a grid operator balances the supply and demand for electricity), which further limits grid operators’ options.
The subject of a wider transmission area is explored further in our related post “Ultra High Voltage (UHV) Transmission is the Renewable Energy Interstate“
In addition, we lack transmission resources (“interconnects”) in many areas, which prevents useful trading of power among neighbors and leads to congestion losses. This is exacerbated by the separation of our three interconnects (Western, Eastern and ERCOT in Texas). Many areas lack ancillary services markets, so reserves and other functions cannot be put out to bid continuously to support the grid.
Finally, many grid planners do not have access to wind forecast data — or fail to incorporate this data into their planning. Or, they plan using old-fashioned one-hour increments (instead of 5- or 15-minute intervals), which also limits flexibility.
So saying that “storage and demand-side management” are the only options is a white-wash. We have a LOT of ways to improve on this issue.
So, both articles tell part of the story: natural gas turbines do in fact ramp up and down more quickly and easily than other thermal plants. This provides the grid with flexibility, which is necessary for the greater integration of wind energy. However, NG turbines are not necessarily the cheapest way to provide flexibility to the grid. That honor goes to simple fixes like:
- introducing wind forecasting
- widening balancing areas
- establishing regional markets for energy, capacity and ancillary services
- strengthening transmission links within a balancing area and with neighbors
For further reading on why the whole issue of variability may be somewhat overblown (pardoning the pun) see our related post “Why Wind Intermittency Is Not a Big Deal“.
This piece was originally posted on the Clean Technica website.
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