Geothermal resources provide about 3,440 MW of power to the United States electrical grid as of early 2014.
>”In a recent report, the Geothermal Energy Association explored geothermal power’s unique values that make it essential to the U.S. energy mix. These plants have the same important baseload qualities coal now provides for over two thirds of the electric power generation in the nation. Geothermal can be a high-value substitute for baseload fossil fuel or nuclear power plants, providing firm, clean power 24 hours a day regardless of extraneous conditions.
“As state and national policies move to significantly reduce climate changing power emissions, geothermal is a baseload clean energy that can replace baseload fossil fuels at a minimum cost to the power system,” says Karl Gawell, GEA’s executive director.
Gawell explains that as the grid uses more variable energy resources, which it most certainly will, the flexibility of geothermal energy is an attribute that regulators are still learning about. “Flexible geothermal can help firm the system, allowing for imbalance, and is able to provide supplemental reserve,” he adds.
The U.S. continues to make strides toward a cleaner energy mix largely through wind and solar contracts to meet goals of state Renewable Portfolio Standards. This creates a greater need for firming power, and although geothermal can provide this as well, it could get lost in the mix if natural gas becomes a fallback to offset intermittency.
In his 2014 State of the Union address, President Obama called natural gas “the bridge fuel that can power our economy with less of the carbon pollution that causes climate change.” Geothermal energy, too, provides the same stabilizing function as natural gas and comes with unique environmental and economic ancillary benefits. Ancillary services support the transmission of electricity from a supplier to a purchaser and include scheduling and dispatch, reactive power and voltage control, loss compensation, load following, system protection, and energy imbalance.
A geothermal plant can be engineered to optimize these services. In most geothermal plants built today, operators can increase or decrease the amount of power being generated in order to match load requirements — such as making up for gaps caused by intermittency. Geothermal energy and natural gas play a similar role to the power grid with the capability to dispatch, or to change a facility’s power output by ramping up or down depending on system needs.”<
See on www.renewableenergyworld.com