The move to a broader mix of sustainable energy sources is a difficult transition that utilities around the world now face. Among the unintended consequences of hooking alternative power sources to the grid, such as solar and wind, is that a portion of the electricity produced by renewables often goes unused. In the industry, this is the equivalent of energy being wasted. The problem is timing, literally.
Do you see any lights?
Running a power grid operation is no easy business. In addition to the enormous infrastructure required to generate and deliver electricity to our homes and businesses, utilities are required to deal with pricing pressures caused by complicated market forces—ranging from weather conditions to whether you have a solar roof at home. For perspective, the utility industry, which is the largest operator of solar panels, must cope with balancing the grid during periods of both excessive renewable generation (which subsequently cannot be transferred) and peak periods of excessive energy demand, all within a 24-hour interval.
How California Wastes Enough Carbon-free Electricity to Power 45,000 Homes for a Year
A few days ago, Press Enterprise reported that California’s “Increasing amounts of wind and solar energy are being wasted or ‘curtailed’ because no one can use it.” The article was based on data from California Independent System Operator (Cal ISO) on the sources and uses of electric power in the state. It highlighted that “305,241 megawatt-hours of solar and wind electricity were curtailed—a loss of enough carbon-free electricity that could have powered about 45,000 California homes for a year.”
Interestingly, they indicated that this waste was nearly double the amount of sustainable electricity lost in 2015, which arose during the period when California utilities increased the power produced from their large solar power installations by 28%. The article quoted Cal ISO as calling the situation, “Unsustainable as more big solar plants and rooftop systems come online and create a surge of power late mornings and early afternoons.”
Variable Energy + Peak Periods: An Unsustainable Formula
Timing is rarely perfect for the business of power delivery. The clean energy produced by the solar panels on your rooftop during the day is of no use when the sun sets, and you turn your lights on. An efficient system to store this energy is not yet on the market. Your surplus solar energy goes back to the grid during the daytime so it can be used right then. Wind power suffers the same problem of variability but in a much more unpredictable fashion: power is only generated when the wind is blowing. The problem of renewable intermittency becomes evident (and quite painful for utilities) when everyone is using electricity, and none is being produced in excess.
In a free market system for electric power, such as California, this imbalance of power supply and demand “Forces the electricity prices on the state’s real-time marketplace to plummet, leading some power-plant operators to shut down until demand catches up with supply later in the day,” as stated by the Press Enterprise article. This is where the waste of sustainable, carbon-free electricity produced by solar and wind occurs—which is equivalent to the lost inventory of a rental car that goes unrented or a hotel room that remains unbooked.
Earlier this year, we wrote that Germany experienced a similar problem last year; clean electricity was being wasted because nobody could use it (Innovative Things Happening in Sustainable Energy). The problem of unused carbon-free power in Germany has been compounded by their Energiewende (“Energy Transition”) plan, which is rapidly transitioning coal and nuclear energy plants. Just last week, the online journal Quartz published an article about “Germany’s aggressive shift away from fossil fuels and nuclear power has pushed the country’s two largest utility companies deep into the red.”
Utilities and Renewable Energy Companies Need to be Allies for Sustainability
According to the Press Enterprise article, the excessive clean power that is wasted will continue to increase unless “changes are made.” The solution they give—to expand the market for surplus sustainable electricity by selling it to neighboring states—does not solve California’s problem of complying with the state’s law of supplying 50% of electricity from renewables by 2030. Furthermore, this “sell-the-excess” solution is just a short-term remedy. California’s neighbors will eventually face the same problem of unused clean electricity that Californians face today as they move to carbon-free production—both through centralized generation by utilities and off-the-grid by consumers.
Several months ago, we wrote an article (Hydrogen, Wind and Solar: Allies for Sustainable Energy) explaining that the way forward for an industry whose traditional business model of centralized power delivery is under increasing pressure, is to work alongside innovators in off-the-grid clean energy production, including wind, solar and hydrogen. We wrote, “Solar, wind and hydrogen make a powerful triad when it comes to obtaining always-available (24/7), clean, and affordable energy.”
We also explored how the issue of power variability posed by solar and wind can be mitigated with Hydrogen 2.0 to help utilities deal with peaks. If both sources feed the same grid, the flow of energy can be maintained at a steady state. Conversely, when demand for electricity is low or weather conditions are excessive, these two sources may generate excess electricity. Rather than being wasted, the energy surplus can be used to produce hydrogen from water, which can then be stored and subsequently used to produce electricity when solar and wind are not available. In this manner, hydrogen perfectly complements renewables by providing a way to “store” excess energy.
A well-coordinated energy sourcing and delivery system would never produce too much of a good thing. We are getting there, and that is positive news for everyone.
As the Hydrogen 2.0 ecosystem gains momentum, we’ll be sharing our views and insights on the new Hydrogen 2.0 Economy. We also update our blog every week with insightful and current knowledge in this growing energy field.