I can see huge wind machines turning in what seems like slow motion from my upstairs bedroom window. These turbines, located at the National Wind Technology Center about 10 miles (16 km) away, are at the vanguard of a major shift away from nuclear and coal, and toward gas, wind, solar and geothermal.
It’s not that we haven’t ridden this trend toward renewables before. Some of the elder statesmen among us can recall the U.S. energy crisis of the late 1970s, where we saw a surge of interest in solar and wind generation, particularly in California.
At the Pacific Gas and Electric (PG&E) R&D offices in San Ramon, California, where I was working, we focused a lot of our attention on the nearby Altamont Pass. Wind developers were putting together a collection of wind turbines in what soon would be called a “wind farm.” They were on a tight schedule to connect to one of PG&E’s 230-kV lines before the tax incentives ran out. But they had a problem: PG&E’s operating department maintained that there wasn’t enough available line capacity based on thermal constraints. Of course, the wind developers quickly shot down that argument, because utility engineers were using a static rating based on a 1.5-mph (2.4-kmph) wind speed, and the turbines didn’t even start generating until the wind speed got up to 14 mph (23 kmph).
To get things moving, PG&E’s R&D department, with guidance from the Ames/NASA Research Center, built a small wind tunnel and showed that the transmission line in question had a lot more current-carrying capacity than assumed. The operating department finally agreed, and the Altamont Pass wind farm, commissioned in 1981, became, for a while, the largest wind farm in the world. Even today, this location has the largest concentration of wind turbines in the world.
That’s just one example of how individual utilities and system operators continue to responsibly integrate wind and solar into the legacy grid. The daily issues are complex and the solutions are remarkably innovative, but most of this behind-the-control panel activity is completely unknown to most ratepayers. Even more has been going on at the industry level. For example, 20 years ago, the non-profit Solar Electric Power Association (SEPA) was formed mostly by electric power utilities, and today, SEPA’s board of directors is predominantly made up of utility representatives. SEPA’s stated goal is to increase the mix of solar in the U.S. energy portfolio.
Similarly, the Utility Wind Integration Group (UWIG) was established in 1989 to provide a forum for the critical analysis of wind technology for utility applications. As with SEPA, a large percentage of UWIG membership comes from the utilities and system operators. As a result of all this activity, today we have the great luxury of well-funded committees, organizations and research teams all working together to shape solar and wind into useful resources.
We are also getting unexpected help in integrating renewables from the gas industry. Because of new extraction technology, natural gas is becoming abundant and relatively cheap. It also has better environmental acceptance and flexible electric generation applications. As a result, natural gas is considered not only a basic resource in itself, fast-ramping gas generation also can help fill in for wind and solar when the wind doesn’t blow and the sun doesn’t shine.
But even with all this structure and effort, the laws of physics aren’t to be violated. We’ll need to guard against political efforts to dramatically increase levels of renewables over short time frames. Unless somehow mitigated, resources with poor or erratic availability factors can lead to an overloaded and unstable grid.
For example, a hurriedly called meeting in February brought California utilities, the system operator, regulators and consultants together to discuss the state’s current power crisis. Apparently, there is too much customer-located solar generation coming on-line, due to taxpayer- and ratepayer-provided incentives, and the system can’t adapt to handle the erratic influx of power. Oddly, no one knows how many installations are behind the meter, not even the U.S. Energy Information Administration. To make things worse, several coastal gas-powered generation units are being shut down because of environmental regulations, greatly reducing grid flexibility.
The California grid definitely feels the bumps when the sun comes up or goes down, so much so that utility experts are stating publicly that they see blackouts on the horizon, within the next couple of years, unless action is taken. Unlike most other regions, by law, the California grid must accept qualifying renewables as they are offered, without regard to the impacts on the system. You’d think that the obvious near-term option is to put a moratorium on new solar connections, but good luck with that one. The partnership of politics and over-zealous advocacy is firmly in charge, at least until the lights start going out.
As expected, no specific solutions were proposed, but in typical bureaucratic fashion, attendees were asked to come back in a few months to discuss the issue some more. Time will tell whether the explosion of local solar sources is fomenting a looming crisis or is merely a tempest in a teapot.
So we push on, solving issues as they arise. We’ve been at this for 30 years. Success to date has shown that utilities and grid operators have what it takes to develop and deploy appropriate grid stability and dispatch tools, providing they have access to the proper balance of generation, storage, load-shedding and load-shifting options. But making those options available in sufficient size and number will take time and resources, things that regulators, policymakers and myriad advocacy groups continue to neglect.
