He and the other panelists agreed that hydro is an essential part of the power generation mix and has a vital role to play on its own, as well as in backing up intermittent renewable resources.
In The Multiple Uses of Hydro – Reliable Baseload, Flexible Peaking, and Clean Energy Storage, five panelists with expertise in hydroelectric power discussed how hydro can be a reliable baseload technology, provide flexibility for peaking, and is the single largest resource for energy storage. In fact, as Brian Murtha with Black & Veatch pointed out, pumped-storage hydropower is by far the single largest source of energy storage in the world. Pumped-storage hydropower provides a total storage capacity of 160 GW, and CAES, gas and batteries combined provide less than 1 GW.
Sergio Souza with GE Renewable Energy Hydro called hydropower the solution for the new grid to come. He said: “We should not see wind as the enemy of hydro, because for every wind turbine you have installed, you need hydro to support it.”
Southern Company has 2600 MW of hydro, with seven of these 32 plants more than 100 years old. Over the next 10 years, the two divisions of the company plan to reinvest a total of $2.2 billion in the hydro fleet. With regard to pumped storage, Southern Company owns Wallace Dam, with close to 500 MW of pumped storage capacity, that began operating in 1984 and is still running today with original equipment. And the company owns 20 per cent of the Rocky Mountain pumped storage plant. Additionally, Southern Company is investigating two strong project sites for future pumped storage development, which could provide 1000 to 1500 MW of potential. The hangup to developing one of these, Johnson says, is the valuation of pumped storage in this ever-changing market.
Carl Atkinson with Voith Hydro said hydro is a cornerstone of the US energy market and still a very viable building block around the world. He agreed that pumped storage is a really viable asset for continuing use in power generation, saying hydro can be used to store energy from all the other renewable resources being built and release that energy when it’s needed. In Europe, Atkinson said, pumped storage is being used to respond to very quick grid faults.
Kevin Young with Young Energy Services discussed the fact that traditional hydro has always been thought of as a peaking resource but now it is becoming more baseload than it ever way. Young also said the U.S. hasn’t built new pumped storage in decades because of financing. And the U.S. can’t meet its renewables criteria unless adequate storage is available. Because pumped storage doesn’t generate new power, it’s like a giant battery in the system. In fact, batteries and pumped storage are complimentary, with batteries tending to be more distributed and large pumped storage tending to be more system based.
Souza said that batteries are trendy and they have their space, and pumped storage has its space and they’re different. Atkinson said batteries are being brought in to make traditional hydro plants more responsive to the needs of their local grids. For example, installing batteries in the switchyards effectively expands the operating range of the hydro equipment.