- Jan 25, 2022 2:09 pm GMT
The US transition to renewable electric generation is proceeding down a path which assures that electric rates will rise. Wind and solar are “source of opportunity” generators, producing electricity when the wind blows and the sun shines. They are intermittent, unreliable, non-dispatchable sources of electricity, which require backup from conventional generation sources or storage when they are not producing electricity. The renewable generating capacity connected to the grid is redundant capacity, in that it cannot replace conventional generation capacity, though the electricity it generates displaces electricity generation from conventional generators.
This duplication of generating capacity increases electricity infrastructure investment, thus increasing required return on investment and consumer electric rates. The addition of the renewable generation combined with the requirement to retain conventional generation, in the absence of electricity storage capacity, decreases the quantity of electricity generated by the conventional generating plants while increasing the cost of the electricity they do generate, since plant investment must be recovered from decreased generation volumes. The subsidies and incentives provided for renewable generation reduce the cost of the electricity they produce to consumers by transferring that cost to taxpayers, most of whom are also consumers.
The renewable energy industry is very quick to point out that the cost of the electricity it produces is declining and, in some cases, is cheaper that electricity produced by conventional sources. However, this is a faulty argument since renewable electricity is not reliable and dispatchable. The renewable energy industry asserts that providing transmission access and the storage capacity necessary to make renewable electricity dispatchable is the responsibility of others, such as the utility industry. This position allows the renewable energy industry to maintain the fiction that renewable energy is low cost and would result in rate reductions. Transferring this responsibility to the utilities also allows the renewable energy industry and its allies in government and the media to blame rate increases and grid unreliability on the utilities.
Logic suggests that the storage capacity required to render renewable generation reliable and dispatchable should be co-located with the wind or solar generation. The generators produce DC electricity and batteries store DC electricity. Inversion to AC power at transmission voltage would occur when the capacity of the generation / storage facility was dispatched. This approach limits losses to the in and out losses of the storage system and the energy lost in the inversion to AC power at grid voltage.
Remote location of the storage required to achieve reliability would require that the DC electricity generated at the site be inverted to AC electricity at transmission voltage, transmitted to the storage facility, rectified to DC electricity at storage voltage for storage, then inverted to AC electricity at transmission voltage again for dispatch. These multiple DC to AC to DC to AC conversions cascade the losses associated with each of the conversions.
Regardless of the transmission and storage approach pursued, the conventional generation fleet cannot be decommissioned until a fully dispatchable alternative is in place and operating. However, even after the renewable generation and storage infrastructure replaces the conventional generation infrastructure, electricity rates would still likely be higher until the cost of the required storage infrastructure declines significantly.
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