ERCOT, the Texas power management organization, sent out an urgent plea this weekend for everyone who could to reduce power usage as much as possible. The system was strained at the seams. Wind and solar had both gone off line, natural gas supplies were not great, and peak usage pushed the rest of the generation capacity to its limits. The state now gets 23% of its power from wind, most of which had turned into turbine-cicles. That left coal and natural gas for power generation, since the state doesn’t have any commercial nuclear power plants.
I think the time has come to revisit nuclear, especially the possibilities of small, regional or even just urban nuclear power generators. Perhaps with a less inter-connected power grid, or perhaps not. Being able to transfer electricity from places with it (up here) to places that need it (down state) can be very, very important.
My ideal power grid would have ten or twelve city-sized nuclear power plants to supplement the coal and gas plants currently in use. Wind is OK, and long-time readers know that I like the small wind-chargers for house or business use. Those make very good sense. But that does not scale up well, leading to things like the problems the country experienced this past weekend. Solar has its place, again with limited size applications. Solar panels buried under snow, or deprived of sun by thick clouds for days at a time are expensive, flat, and useless. I will not rant about the environmental costs of large solar and wind generation arrays. That’s for a different place and time.
But nuclear I like. I grew up near a nuke plant. It put out less radiation than did the coal-powered plant a few miles away. Nuclear is clean, it is safe, and it can be scaled up or down depending on the application. We’ve come a long way from the technologies of Three Mile Island (which never leaked) or Chernobyl (which was Soviet and managed by an [very rude word here]). Fukushima survived everything it was supposed to, and a little more. It was the “oh Lord that can’t happen” failure chain that did it in. {The back-up, back-up, emergency system failed because the protective walls were not quite high enough to keep the tsunami out.}
Put the new, smaller, safer nuclear power plants near some of the cities. Perhaps not down on Hurricane Central, because people will fret about “what will a Cat 6 hurricane do?!? Three headed fish!!!” and so on. But say Wichita Falls, Midland, San Angelo, north Texas, one up here or down in Lubbock, El Paso, and the like. Dump the wind turbines for the most part, and not so much solar except where it makes sense. Shift the grid to a more regional system, while retaining ways to link-up to other regions for things like ice-storms, hurricanes, tornadoes, or that derecho thing that hammered the Midwest last summer.
Having shorter transmission routes reduces the risk of bad things happening to those lines, and cuts the cost. Nuclear is a lot more reliable than wind and solar, so you can decommission the back-up coal and gas if the activists absolutely insist. I’d do the other way, keep coal, use gas for home heating and the like, and nuclear for every-day and back-up. (I’m not a fan of all-electric for heating. I have my reasons.)
Will it cost money? Yes. Will it take an act of Divine Intervention to get past the EPA and other environmental activist groups? Alas, yes. Does it make too much sense for politicians? Probably. Would it help prevent the rolling black-outs Texas has gotten to enjoy in the past and happened Feb 13-16? Yes. Does it harden the grid against attacks? Not my specialty, but I’d say a qualified yes.
A gal can dream.
Cat Rotator's Quarterly 
You’re making way too much sense… I spent about 15 years in the nuclear business mostly in Health Physics and Operations. I didn’t realize Texas was mostly on its own for power. Unfortunately the ideology over reality crowd would fight it tooth and nail.
Until about 20 years ago, we were fully self contained. Then stuff happened, and parts of western Texas (for the most part) hooked onto the national grid. People started regretting that 8-9 years ago, when a transformer failure in AZ led to generator shut downs that turned into a cascade reaction that left El Paso in the dark at 20 F for several days.
Thomas Edison used fear-based tactics in an attempt to defend his DC-based distribution system and turn the public against the AC-based system promoted by Westinghouse and Tesla. He didn’t get away with it. If today’s political & social climate had existed back then, he would probably have gotten away with it.
Much of the fear of nuclear is because the apocalyptic associations of nuclear weapons have been psychologically transferred onto all things nuclear. Probably the only reason that we have medical MRI machines (the technology was previously called nuclear magnetic resonance) is because a smart marketing guy at GE changed the name.
True, that’s the source of a lot of the fear of nuclear power. But not all of it. Three Mile Island, Chernobyl, and Fukushima demonstrated that older nuclear power reactor designs can be extremely dangerous. At Three Mile Island the safety systems worked, but as I heard the story that was a matter of luck and extremely over-designed hardware — the reactor operators really messed up their initial response to the transient, but the reactor design had so much tolerance for error that it lasted long enough for them to realize they’d screwed up and change course.
I am all for nuclear power, the sooner the better. Show me a design that’s compact, efficient, and safe, and I’ll be all over it. I want to see such plants providing power all across the planet, as many as we can fuel. I just can’t ignore the fact that an accident at a nuke plant has the potential to endanger large numbers of people and irradiate large areas of land.
If you really look at Chernobyl, the fatalities came from the people who were fighting the fire and on-stie in the first three or four days. The kids who got thyroid cancer or had other thyroid problems were planned for, once the rest of the world knew what to expect, and they seem to have come through as OK as one can. The area around the plant is now one of the healthiest wildlife reserves in Europe, with large populations of healthy plants and critters. [Full disclosure: DadRed was involved in some of the public health measures in Belarus in the late 1980s – mid-late 1990s until politics chased his group out.]
That’s (relatively) easy. Take the reactors that the Navy buys for subs and carriers and put them into large scale production. No known problems with them in almost 60 years of service, including two that are now on the bottom of the ocean due to other problems.
This was supposed to be a reply to Wolfwalker’s request for a reliable reactor design.
There were however, design practices faults. An indicator showed the position of a valve _actuator_, but there was nothing to show the actual valve position. The operation instructions didn’t include how to fly with one instrument out, and there might not have been enough redundancy. And the only phone line could be blocked by a flood of incoming calls, preventing the operators from calling the support engineers at (I think) Babcock and Wilcox.
It really didn’t help that the Three Mile Island accident happened at the same time as The China Syndrome movie came out. A friend (working for General Atomic) saw that movie, and on the way home, TMI hit the news. That put a lot of builds on hold and stopped orders for new ones. It took three years for GA to get around to laying off his group, but the omens were set.
I worked summers for a steel company that provided a lot of structural pieces for nuclear plants in the Midwest in the early ’70s.. These would have hit end-of-life, but there was a lot of nuclear generation in that area. Sadly, California had little, and between unfortunate locations (hard to find a site with water cooling that doesn’t have a faultline running under it) and some of the general incompetence shown by PG&E, they were down to one active plant, with plans to shut it down. The environazis hating nuclear plants didn’t help.
I don’t know if Oregon ever had any nukes. Hydro is getting clobbered by the save our fishies groups, and the recently built solar farm seems to have 50% offline at any given time. The local farms use mechanical tracking, which might be fine if you really need early morning and late afternoon summer power, but the ranchers use south-facing systems for their grid tie arrays. (I’m pretty sure that excess panel space is cheaper than thousands of motors and tracking rails.) That’s what I have for our pumphouse/backup power system. Even before the 50% issue, you could see individual rows go wonky as the tracking system failed in spots. Arggh.
A gal can dream.
Yep, but there are too many idiots out there for that dream to come true. 😡
Long ago in a galaxy 20 years away, there were news stories like this:
“A nuclear reactor designed to generate power in the basement of an apartment block is being developed in Japan. In the past few months government-backed researchers have been testing a fail-safe mechanism for the reactor, which will close down automatically if it overheats.
“The Rapid-L reactor was conceived as a powerhouse for colonies on the Moon. But at six metres high and only two metres wide this 200-kilowatt reactor could relatively easily fit into the basement of an office building or apartment block, where it would have to be housed in a solid containment building.
“’In the future it will be quite difficult to construct further large nuclear power plants because of site restrictions,’ says Mitsuru Kambe, head of the research team at Japan’s Central Research Institute of Electrical Power Industry (CRIEPI).
“’To relieve peak loads in the near future, I believe small, modular reactors located in urban areas such as Tokyo Bay will be effective,’ he says. Kambe’s research is being financed by the Japan’s Atomic Energy Research Institute.”
https://www.newscientist.com/article/dn1186-mini-nuclear-reactor-could-power-apartment-blocks/
One minor correction Texas has four Nuclear units, two at the South Texas Project out side of Houston, and two at Comanche Peak out side of Dallas. Both Comanche Peak units are at 100%, One of the South Texas units is at 100%, the other is down, presumably for maintenance.
Full disclosure, I have worked in the nuclear industry both commercial power and government facilities for over 30 years. Most recently I was a very small cog in the design team for the AP1000 passively safe plant. My personal opinion was that the financial problems on that plant were caused by management of Westinghouse and the Constructor, not any fundamental problem with the basic design.
There is a SMR (Small Modular Reactor) design working through the NRC COL (Combined Operating License) process. The NuScale Power design is a small (40MWe) PWR (Pressurized Water Reactor). Terra Power’s traveling wave design apparently hasn’t started the licensing process yet. A consortium of small utilities and DOE are pursuing licensing of a multi unit NuScale plant in East Idaho. However, the design has not been approved by the NRC. With the current administration, I don’t expect much progress on licensing approval from the NRC until a more nuclear friendly administration is installed.
Thank you for the correction. The last I had heard, two of the four were out of commission. That might have been a temporary “for repairs/routine work” notice.
According to a story, South Texas #1 went down for low steam generator levels. The NRC report said cause unknown, but an article in the Washington Examiner says that it was due to lack of winterization. (Apparently, a bunch of NG well heads also froze, taking some of those plants offline, too. ) Who’d have thought that a power plant near Houston would need freeze protection?
What a mess. Can we blame Al Gore for the Texas Freezening?
Nuclear plants convert the energy to heat, and then to steam, which powers turbines. This means they need to be located on rivers with plenty of flow, or on oceans or giant lakes.
We need to change our policy on once-through fuel cycles. They extract less than a tenth of the available energy, and the waste remains dangerously radioactive for millenia because of what’s not used. Breeders use less than a tenth of the fuel, and tha radiation in the waste tails off in only centuries.
Having the reactors nearer the power consumer reduces transmission losses. Over long distances, the power loss in transmission can exceed 50%. A lot of work went on, unannounced, in the 80’s and 90’s to reduce this. Higher voltages, million-volt DC lines, and semiconductors (transistor-like devices) switching power within each half-60Hz cycle let the power engineers do amazing things–and also make everything more vulnerable to EMPs.
Finally, nuclear plants of whatever size cannot peak. The need to be run steadily, with slow adjustments to their power. Run them up too fast and you invite runaway. Shut them off too fast and you can’t restart them for 36 hours or more.
Natural gas is ideal for peaking–with one caveat. Gas turbines run on the hot combustion gas, and peak nicely, but you can’t get 50% efficiency from them. To extract more energy, you need to use the still-hot exhaust to boil water, and put the steam through a turbine. The steam part can’t peak, and adjusting it too quickly will reduce the efficiency of turbines tuned for a certain steam supply. Thermodynamics rules, even more surely than Newton. The only thing more powerful is an alloy of human stupidity, human pigheadedness, and human lust for power over others.
“Nuclear plants convert the energy to heat, and then to steam, which powers turbines. This means they need to be located on rivers with plenty of flow, or on oceans or giant lakes.” – No, it’s just more convenient that way. Palo Verde is pretty much in the desert outside of Phoenix. They buy treated sewage water from Phoenix, have their own water reclamation facility and water has not been an issue with them, enough that they run 3 reactors at about 1200 MWe each.
And made a mint selling power to California during Gavin’s last power emergency.
As a business model, installing baseload around but outside California with good grid interconnect access and solid surge capacity (maybe nuclear plus gas turbine plant that share cogen) would make a lot of sense.
I don’t know that any have been built, but there have been a number of proposals for air-cooled reactor designs.
I know there was at least one pilot High Temperature Gas Cooled reactor (HTGR) at Fort St. Vrain in Colorado, and I believe there was a European Fluid bed design, but I don’t know if that ever got beyond experimental.
The folks at NuScale have received NRC approval and they have the first plant using this technology in progress in Idaho Falls ( https://www.nuscalepower.com ).
Basically, the power module, with the reactor vessel, steam generator, and containment, is factory-built, sized so it can be shipped to the site where the cooling pool and containment building have been built with space to hold multiple cores. Power module core design features natural circulation, such that if power is lost it shuts itself off and cools itself down, all with no additional water, operator input, external power or even battery power.
Modular at 77 MW per module so it can be sized and expanded easily since they leave room in the pool, and unlike existing plants that get designed uniquely so each plant has to be approved one by one, this design itself has been approved.
The website notes that one use for the heat is desalination. Since desalinated water can be stored, a desalination cogeneration plant might be used to mimic peaking, if the desalination part were oversized. To peak to the grid, reduce the power to desalination, drawing the stored water reserves down for a few minutes. To de-peak, shunt the excess to the desalination plant.
There are many large devils in the details, but it does provide opportunities.
Where a plant is near a city, community (utility) steam is also possible, since the waste heat from the plant will often be enough to create saturated steam. Only a little extra heat (at higher temperature) will provide the live steam needed for distribution).
In the USA, the largest such system is in central and lower Manhatten. The steam is used for heating, cooling (absorbtion cycle) and other things, even for pressing clothes.
If a nuclear plant were located near a change in elevation, the method used in CA at the San Luis Reservoir and a few other places could be used to shift peak and store power.
At San Luis they have two reservoirs, one higher than the other; during off-peak they pump water from the lower into the upper, then during peak demand periods they release water from the upper through hydroelectric turbines down into the lower and put that power on the grid.
Since they are open there are evap losses so it’s not a fully closed loop system, but it’s pretty straightforward, and the tech needed is pumps and valves and hydro generators and a time-variable cost/price of electricity.
Obviously the flat parts of the US could not easily use this method, and Texas is overall pretty flat. I guess they should have not let the US chop off the parts of Texas that went all the way up into the Rockies…
Hydrostorage is great, but you need the water (there will be evaporation) and you need to face down the greens. The Storm King pumped storage project would have been the perfect complement to Indian Point, making the best possible use of the steady megawatts, 24 hours a day. But the greens shot it down, and Con Ed had to find other ways to cover the varying load. Enter Big Allis, the generator that could have been designed by Congress. It played a part in several major blackouts, and had to be rebuilt every time it had an unplanned shutdown. It probably has more Google search results than Wales.
Very true – watermelons hate all dams. That’s why there has not been one hydro site installed in CA for a very long time.
I remember that time. They shut down the proposed dam on the American River in the early 1970s. They’ve been hobbling any attempts at updating anything besides their pet green ideas since then.
Near Klamath Falls, we’re losing the old COPCO dam complex, responding to pressure from tribes nearer the mouth of the Klamath River forced that removal, plus Pacific Power (Warren Buffet’s Berkshire Hathaway owns it) didn’t want to do fish ladders.
Somehow they ignored damming on the Trinity River, which diverted more cold water from the Klamath than our dams. Of course, screwing over flyover country ag interests wouldn’t possibly have meant more than, say 85% of the decision to go that way…
OTOH, we’re getting a pumped power storage installation NE of Klamath Falls. The usual bit about the horrible dangers of 60Hz electricity were considered. Those electromagnetic fields (a) in a quiet area even by local standards and b) never shown to be an issue and c) what in hell are the activists using in their own houses ) all ended up getting ignored. As they should.
Desalination has other benefits – water is a majorly constrained resource throughout the western US, and if one were to put a desal plant in pipe range of LA one could sell all one made.
But it’d have to be down past San Diego in Mexico – in spite of insane unmeetable greenyness mandates and a dire lack of baseload gen capacity, CA is shutting down Diablo Canyon because shut up, Gaia h8er.
Like the Greens getting the nuclear plants in New England shut down, then fussing mightily about the price and reduced availability of power.
Idaho Falls?
Goes and pokes. Oh, out at the Site. Bad reporters! INL is not close to IF! Atomic City, or even Arco, would be a reasonable choice of town.
Explains why I didn’t notice it in local news: just Idaho National Lab doing what’s done there. My husband worked there a while (IT): the INL runs busses from the regional big towns out to the Site.
I just wish they hadn’t stuck the INL on such a recent lava flow. A bit nervous making, though it is historically not explosive.
The NuScale pages that include this first installation, the UAMPS CFPP project cleverly placing a plant to feed the Utah power grid in Idaho, is at: https://www.nuscalepower.com/projects
Over on the Utah Associated Municipal Power Systems (UAMPS) Carbon Free Power Project page they say:
UAMPS is a leader in the effort to develop next generation, carbon free, dispatchable power generation in the United States with its Carbon Free Power Project (CFPP). The CFPP is the nation’s first-generation small modular reactor nuclear plant, to be located at the Idaho National Laboratory near Idaho Falls, Idaho. It will be compromised of 77-megawatt nuclear power modules provided by NuScale Power. UAMPS continues to evaluate options for power plant size, including the 4-pack, 6-pack, 8-pack or 12-pack module configurations, to ensure the best overall cost of energy to meet energy needs of its members. Energy from the project will replace electric generation from coal plants that are nearing the end of their life cycles. CFPP will enable UAMPS and its members to add significantly higher amounts of intermittent renewable energy, especially wind and solar, to energy portfolios. The CFPP, combined with renewables, will enable many members to completely decarbonize their energy portfolios.
I stand corrected, I hadn’t realized that the NuScale design FSER (Final Safety Evaluation Report) was approved for 77MWe as of Aug 28, 2020. However, that does not mean they have a COL. The NRC still has to approve the site specific information prior to starting safety related construction. The NRC is notoriously political and can and has delayed approval depending on how the political winds blow. I won’t hold my breath until the first unit is online.
My first job out of college was working for a consulting company that did nuclear power work, full of very smart ex-GE Nuclear folks – we did stuff like finite element analysis modeling of potential core melty events to prove that curb would work, and worked on new ways to inspect piping for cracks from the outside without slicing them open by clever scanning of the pattern of irradiation of the inside layer, but mostly the company generated multiple metric tons of paper reports to help plant operators satisfy the arbitrary and capricious NRC’s insatiable hunger for wood pulp and printer ink.
I only did that for a short time before I moved over to the semiconductor world, which meant I was the only one that knew a coffee spill could be termed a LOCA, and why it was funny.
In the summers of 1971 & ’72, I worked for Inryco (Inland Steel Ryerson Construction Products) helping with structural steel fabrication orders. We did fab for a couple of plants when I was there, including the Davis-Besse plant in Toledo, and another one on Lake Michigan (Donald C. Cook, near St. Joseph.)
All the steel was certified A-36, and we had to provide chemical and physical certs for (eventually) every piece of steel that went in the bits. It wasn’t too hard for beams and columns, but the plate was a nightmare, since we had to “know” which piece of plate went on which beam and/or column. The certs and multiple copies of the drawings went on each truckload, and we joked that we couldn’t ship until the paperwork outweighed the steel. (As it was, perhaps 5-10 pounds of paper for a 50,000 pound load.)
We learned what a nightmare the tracking was the first year, and the second year (as the situation got worse–I had to go out to the warehouse and stamp anchor bolts with codes for the parts) we added additional charges for the QA program. We were underbid on a portion of another plant, but we learned that the winning vendor shipped their seven truckloads of completed parts without doing any of the QA. At that time, that meant that maybe $350,000 worth of fabricated steel got shipped back to the vendor, who had to scrap them out. Let’s just say that there were a few Schadenboners in our company after we got word of the fiasco. I feel sorry for the project manager. The ones we worked with were under a lot of pressure, and minor delays on our end mapped into major headaches for them.
Oregon used to have a nuke, the Trojan single unit plant, a 4 loop Westinghouse PWR. The state was run by rabid anti nukes by the early 1990’s and they bribed the owners into shutting it down.
What nuke plant did you grow up near? It might have been one I worked at over my 40+ years in the nuke biz. I started at Comanche Peak, then went to Dresden, then went to work for Westinghouse mostly doing design on the AP1000. I was laid off from the CirclebarW ranch in 2017 during the bankruptcy trainwreck and now am working for a small consulting firm still doing nuke work.
The freezing temperatures caused South Texas 1 to trip offline, probably due to frozen sensing lines that had heat tracing failure.
Ft. Calhoun, near Omaha, Nebraska. Alas, they stopped doing school trips just before I was old enough to go.
Very familiar wth Ft. Calhoun. I went out there several times when i worked fot the CirclebarW. Too bad it is another one shut down recently. Nebraska will regret that. I also spent quite bit of time at the Cooper plant further to the south.
Hi Joe, yeah another AP1000 refugee here. Worked for Shaw/CBI on the BOP/HVAC design. What a charley foxtrot. Now I see the Chinese are marketing their version of the AP1000, like we didn’t see that coming.
Yeah, several of us were talking about how soon we’d see a knock-off of the AP1000 being sold by the Chinese. It did not take long.
I was a Westinghouse direct employee working mostly on the BOP power block. My fingrtprints are all over the plant instrumentation for the turbine, condensate, feedwater, and associated components.
Something tells me they’re going to be ‘revisiting’ the whole idea of Nuclear power… Just sayin…
After all is said and done, even if the state commits to expanding existing or adding new nuclear, the majority of the answer in Texas will undoubtedly be new natural gas combined-cycle plants due to ease of approval, Texas NG production capacity, and mostly speed of construction.
The fact that quickly adding NG CC plants also pokes various noisy groups in the eye with a stick while coming in more or less in the same range of $/MWh as solar and wind helps make the political case, but the speed of adding capacity is the biggest thing.
Combined Cycle has laudable high efficiency, but if you use them for peaking, you lose the some or all of the steam cycle benefit.
Abso-DAMN-LUTELY!!
Howcome nobody mentioned Pebble Bed Reactors?
It uses pressurized Helium, Nitrogen, or even Carbon Dioxide to drive the external turbine.
The report I saw Back When said that if the gas flow were stopped, the whole vessel heated up to about 1500 degrees, and stayed there. No melt-down, no leak… no problem!
Reckon that the cooling side of the loop could even be direct-to-air, obviating the need for water.
The maintenance consists of drawing one of the spheres that fill the vessel, checking its level of radioactivity, and then either returning it into the top, or replacing it with a new one.
https://en.wikipedia.org/wiki/Pebble_bed_reactor
I wanted such a reactor, but couldn’t figure what to do with the extra one to ten megawatts….!
Eric,
Pebble bed reactors looked promising at the 15 MWth (~5 MWe) level the test reactors ran at, but when trying to scale them up to a more useful size, the designers began to run into problems. So many in fact, the projects were dropped in the West, and I think even the Chinese are not doing much there any more. One of the Westinghouse guys on the South African project I talked tosaid that the best course would be to build a series of increasingly larger PB reactors and run them for a few years to iron out scale up problems just like they did with PWR/BWR reactors in the 1950’s and early 1960’s. The pressure for immediate commercial success is too great for corporations to do this on their own, and the anti-nuke political forces amke it hard for governments to subsidize this process
I’m awaiting the day when every residential structure will have its own solar cell array.
However, apparently large electric companies can restrict independent use of solar panels.
Interviewed by the online National Observer (posted February 12, 2019), renowned linguist and cognitive scientist (etcetera) Noam Chomsky emphasized humankind’s immense immediate need to revert to renewable energies, notably that offered by our sun.
In Tucson, Arizona, for example, “the sun is shining … most of the year, [but] take a look and see how many solar panels you see. Our house in the suburbs is the only one that has them [in the vicinity]. People are complaining that they have a thousand-dollar electric bill per month over the summer for air conditioning but won’t put up a solar panel; and in fact the Tucson electric company makes it hard to do. For example, our solar panel has some of the panels missing because you’re not allowed to produce too much electricity …
People have to come to understand that they’ve just got to [reform their habitual non-renewable energy consumption], and fast; and it doesn’t harm them, it improves their lives. For example, it even saves money,” he said.
“But just the psychological barrier that says I … have to keep to the common beliefs [favouring fossil fuels] and that [doing otherwise] is somehow a radical thing that we have to be scared of, is a block that has to be overcome by constant educational organizational activity.”
(I still think he’s putting it mildly.)
The current system here in B.C. has each recipient building’s entire electrical delivery relying on external power lines that are too susceptible to various crippling power-outage-causing events (e.g. storms and tectonic shifts).
Clear skies permitting, I can really appreciate the liberating effect of having my own independently accessed solar-cell power supply, especially considering my/our dangerous reliance on electricity. And it will not require huge land-flooding and potentially collapsing water dams.
There are places where passive solar works, as do panels. One problem is that in some cases, fire codes for residential dwellings do not permit roof-top arrays. This might be changing as technology changes. There are also places where residential wind-chargers work very well for much of the year.
Batteries, the need for transformers or dedicated DC appliances, and the (in my region) night time calms and high-pressure ridges that lead to calm winds are all arguments that can be expensive to overcome. Small nuclear could be a very good, green, power source that would help in places where climate and tectonics permitted.
Thanks for the note.
I personally don’t have a big problem with nuclear-powered steam-turbine-produced energy, assuming the plants are not as prone to meltdown (etcetera) disasters that occurred in the past (albeit foreign).
If you only buy power when the sun doesn’t shine, the power utility still has to have ready (spinning) reserve to cover those times. That means the plants must be built, maintained, and run at poor efficiency while you’re drawing power from your unreliable solar panels.
Power transformers designed to step down from (say) 22 kV local transmission to 220 V customer service can be efficient, but if you run power backwards through them, they will waste a fair fraction of power as heat. To make them efficient both ways will require more copper and more iron … more cost.