With increased efficiencies and price drops, rooftop solar has the potential to provide 40% of all National electricity demand (according to a recent article in Nature Magazine). Unfortunately, greedy Utility companies (who often cannot meet demand and force energy “blackouts”) are conspiring to make homeowners pay an onerous tax to them in exchange for providing an energy grid (thereby killing rooftop solar incentives). Microgrids and home battery backups can provide partial solutions (and offset Utility storage issues), but Utility regulators also need to bop Utilities, who seek to be sole-source solar power providers.
Rooftop solar has been derided by energy utilities (here in California, PG&E and Southern California Edison) as being “inefficient” and of “free use of their power grid”. Meanwhile, these same energy utilities irresponsibly cause gigantic forest fires (from arcing overhead power lines), and require ever-more energy “blackouts” (cutting power to diminish fire-danger). Both failures occur in times of high-energy demand (highlighting the utilities shortcomings on both fronts). The utilities’ response is to charge rooftop solar an exorbitant grid tax for rooftop solar (about $50/month), while paying a pitifully low $0.05 per kwh for power sold back to the utility grid. One suspects that energy utilities greedily want to be the sole photovoltaic provider, while the rest of us suffer. A broad and detailed look at the energy/global warming situation reveals that while there are some efficiencies in having energy utilities produce renewable energy and a grid to share and deliver this energy, there is a HUGE benefit to encouraging further rooftop solar, much of it “off grid”. By one estimate, rooftop solar could provide up to 40% of the nation’s electricity needs! To accomplish this goal, the State may need to intervene, encouraging cooperation, more efficient HVDC lines, and perhaps even taking over the grid under condemnation. (Schultze,2022),(Trinastic,2016)
The Rooftop Solar with Battery Backup & Generator Option: I have recently seen a complete 7000 watt photovoltaic system, complete with (battery backup and generator) offered for about $24,000 (with 26% through 2022 in federal rebates, or about $6000). At $0.15 per kW off-peak/$0.30 per kW peak (roughly the current rate for electricity in California), let’s say there was a $0.20/kW average savings, with roughly 3000 watts x 8 hrs (24 kwh per day). If all photovoltaic electricity were used or stored, there would be about $1,800 worth of utility savings, for a ($25,000-$6000)/1,800 = 11 year payback (at this point, know that the panels have about a 20 yr life, while the batteries are good for about 8 years). With rising energy prices (and ever-lower photovoltaic and battery prices due to emerging technology), this payback will only get better. It should be said also that 7,000 watts is a great deal of power (I used to offset half my energy bill with a 2,000 watt system), and if a household was using less than 3,000 watts worth, it might not be worth the trouble of going off grid. There’s also the growing benefit of having power when the utility has their ever-increasing “blackouts”, in times of fire-danger or high energy use (usually during the hottest days). Generators solve the problem but are noisy, polluting and expensive. Having an off-grid photovoltaic system allows one to greatly decrease their generator use and generally downsize their generator (some have 7,000 watt generators to power their whole house, I’d probably need a 3,000 watt generator just to freshen up the batteries). Another big plus of off-grid systems is that they combat Utility line-loss (delivery distance goes from miles to feet) and help with renewable energy storage issues. (census.gov,2021),(css.umich.edu,2021),(solarreviews.com,2022),(Greengardenchicken.com,2022)
Why are the Utilities being so hard on Rooftop Solar?: Several reasons, starting with the potential of making the utilities obsolete. The energy utilities have enjoyed an energy monopoly for the past 100 years and are reluctant to give it up. They feel that their energy grid costs them a lot of money (for upkeep) and that rooftop solar needs to help offset these costs (with some merit). The utilities have their own competing photovoltaic (and other) energy sources, and perhaps see photovoltaic as a threat to their bottom line. The utilities own large photovoltaic operations in places like the Mohave Desert, which they argue are more efficient. There is some validity to this argument, since rooftop solar doesn’t always have optimal orientations to the Sun, but then what rooftop solar lacks in efficiency is made up for in sheer size. Additionally, photovoltaics are getting efficient and cheap enough so that orientation is less important. Another HUGE factor is that utilities LOSE about 40% of the energy they produce in HVAC transmission (line loss, mostly from heat, in lengthy power lines)
What should happen to resolve all this: The government (mostly in the form of the Public Utilities Commission, which is often staffed with former Utility officials) needs both utilities and homeowners to solve California’s energy problem. If done properly, California could even supply about 25% of the NATION’S energy needs (mostly in the West). Additionally, many Cities and secondary utilities (such as water and wastewater plants), have the capability of producing energy. If the energy grid (needed for those not off-grid and wishing to “sell” excess energy) stops being profitable for utility companies, the State may need to take over (sort of like inefficient bus or train routes). In time however, the grid may become valuable again (especially if longer power transmission lines are converted to HVDC, lowering line loss). In the “perfect world scenario”:
A) 30% of California households may be off-grid (producing their own power with no need for the grid)
B) 40% may have rooftop solar, be connected to the grid and selling excess power, and
C) 30% with no photovoltaic rooftop, solely dependent on the utility/grid.
If California were to achieve a goal of producing 25% of the Nation’s electricity (about 12 kwh per person per day, or 360 million mw per year), our 13 million households might be capable (at say 30 kwh per day per household) of producing (0.7x13 millionx30x365)/360 billion = 28% of demand. The energy utilities could be expected to produce another 50% (from wind, solar, hydroelectric, geothermal, etc), while cities and non-energy utilities could product the remaining 22%. This is of course a very significant amount, out of proportion with California’s geographic size, yet CA has the population and sun to accomplish such a task (just as it produces a disproportionate amount of the Nation’s agricultural produce). If the other states made similar rooftop and related contributions, we may become an all-renewable Nation in short order. The beauty of HVDC is that it makes us much less battery (and other storage) reliant, since it can efficiently shuttle excess electricity to other states with little line loss.
The Problem with Microgrids: Just about the time we start envisioning a utopian energy-utility-free world with a bunch of neighborhood microgrids, we run into the “small is not always beautiful” problem. For all the talk about “appropriate technology” (small-scale, relatable to small communities, providing local jobs under local control), know that generally, larger entities are more efficient than smaller ones. In the water business, the small utilities fill up with local cronyism and corruption that would sometimes make the larger Districts blush. Things being what they are, about 20% of households may evolve “do it yourself” systems on a single or 2–4 household joint level (pooling excess energy with one’s neighbor) while many may avail themselves of their friendly neighborhood solar store for minor management/repair.
What the Energy Grid should look like: In the water delivery business (also under siege in California) there is a marriage of private wells and surface water managed by water utilities. This has been minimally regulated to this point, but that’s about to change. Private wells are being metered and regulated for “water quality” purposes (actually also to limit over-pumping of groundwater), while surface water deliveries are being restricted on many fronts. The electrical energy picture might look similar to this if the State intervenes. “Private” energy providers (microgrids) may take production pressure of the big energy utilities. Overhead lines may be largely placed underground (to minimize fire danger), and the grid may be set up for HVDC “sharing” (to shuttle excess power to needy areas, thereby minimizing storage need). The energy utilities would continue, but in a more limited form (from the days when the grid was their sole domain). The grid of the future will be taking more energy in, putting less energy out. Generally, energy won’t have to travel such long distances, and be prone to line loss. A kilowatt hour produced at your house might very likely be “bought” by your neighbor down the street, as opposed to a hydroelectric dam kilowatt delivered one hundred miles to a Central Valley home.
Conclusions-Energy Utilities should be more inclusive of Rooftop Solar: If they can’t be, the State should condemn the grid, take it over, and make it profitable (by lowering line-loss, making it fire-safe, selling energy to other States). If that happens, I suppose the energy utility robber barons can take their business to places like Russia, where their heavy-handed and Oligarchical ways are tolerated.