Wisconsin’s electric cooperatives give their full attention every day to providing power for their members reliably, safely, in an environmentally responsible manner, and at an affordable price. One thing helping them accomplish this is that they, and the regional electric grid where electricity is bought and sold, are able to count on a number of different fuel types and technologies for generating electricity. A diversity of power resources helps manage costs in the event of a price spike or short supply affecting any single fuel.
Diversification also involves baseload and non-baseload power sources. Making these resources work together to power your homes and businesses demands continuous attention, just as meeting your immediate needs depends on long-term planning. Generating plants are expensive assets with a useful life spanning several decades.
In areas of the United States served by electric cooperatives, baseload power plants have most commonly been fueled with coal. One major reason is the federal government’s response in the 1970s to international energy worries, with policies and regulatory choices directing greater reliance on coal as a domestic resource in plentiful supply. More recent regulatory choices have combined with abundant—and therefore inexpensive—natural gas to prompt retirement of many of these coal units, but baseload plants are capable of continuous operation for days, weeks, or even months if the economics make sense. And those owned by co-ops (and other Wisconsin utilities) have been designed or upgraded to meet Clean Air Act standards while providing a consistent and steady amount of power.
The diversified wholesale power market serving Wisconsin and numerous Heartland states also provides power from varied sources, blending intermittent renewables like wind and solar into the grid’s energy mix. Renewables are considered non-baseload power because their availability—best expressed as their “capacity factor”—is highly subject to geographical influences. Capacity factor is the industry term for actual output stated as a percentage of what a generating unit is theoretically capable of producing. For June 2018, the government’s Energy Information Administration reported the average capacity factor of U.S. nuclear plants—baseload generation—was 97 percent, compared with 42 percent for wind turbines and 35 percent for photovoltaic solar. (The capacity factor for wind in Wisconsin is a little more than half that nationwide average, which is why you don’t see as many turbines here as in Texas or Iowa, or even Minnesota.) Similarly, photovoltaic solar is popular in Wisconsin but this isn’t the sunny desert southwest; thus our panels don’t operate as steadily. So non-baseload generation output is combined with that from baseload plants to ensure that when our members flip the switch for power, they can count on a reliable and adequate supply.
Energy storage devices such as batteries have come a long way, but they’re still not economically feasible for the average household and they discharge too rapidly to consistently meet consumer needs. Ongoing research will determine when and if storage technologies are viable for use over periods of more than a few hours.
As a member of a not-for-profit electric cooperative you may ask, why is all this important to me? One answer is that a balanced and diverse energy portfolio in some ways resembles a diversified personal financial plan: Varied investments are the best insurance against inconsistent performance. The same is true with sources of power generation. For the best achievable combination of reliability, affordability, environmental responsibility, and safety, we rely on multiple sources rather than put all our eggs in one or two baskets.