"The Texas Senate passed a bill Thursday that leading business interests fear would lead to an age of expensive power and rolling blackouts.
If passed by the House, state S.B. 715 would require all renewable projects — even existing ones — to buy backup power, largely from coal or gas plants.
This would require solar plants in particular to buy backup power to “match their output at night — a time when no one expects them to produce energy and when demand is typically at its lowest anyway,” consultant and energy expert Doug Lewin wrote in an April analysis"
Providing power at night is much more reasonable than forcing an equal/backup gas plant.
Requiring solar to have 2-4 hours battery backup power is a great way to expand grid while still keeping existing plants around. Peaker/backup plants have always had a business model based on high rates. If the law says a solar project must buy into a legacy plant and promise to keep it ready for backup, it’s not totally crazy, as long as it can charge extortionist rates when it is needed. It doesn’t reduce benefit of battery storage, paired with larger solar array.
100 hour storage, like iron air batteries, is cheap but not as economic as mature battery technologies for power arbitrage. Still, if there is a regulation to have 18-48 hours of power reserves, then it is an ok solution. The problem with long term storage with solar is that if you get 6 hours of sun in a day, half to charge, half to sell directly, you only add 6 hours, even if most days you wouldn’t draw down 6 hours at night due to lower demand.
Hydrogen electrolysis is another solution to monetizing overproduction. It can be done more cheaply with methane than water, and still be zero emissions, zero capture and sequestration, with marketable carbon black solid as byproduct. Keeping a bit of H2 onsite, with a fuel cell as backup, or NG electric plant, can be profitable, but all depends on how much you have to pay for backup, and how much profit from use.
Introducing V2G service that pays EV owners to be “the backup” in addition to battery arbitrage revenue is another path, that will happen soon enough, but where some kind of regulatory obligation to have it, makes it happen with more commitment.