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Rooftop solar panels are flooding California’s grid. That’s a problem.
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- Title
- California has so much solar power it's throwing it away
- Published
- Apr 22 2024
- Word count
- 1079 words
From the article:
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Not very surprising. Solar availability being out of sync with demand is the main complaint with that source of energy. It seems to me that if the state wants to push property owners to install panels it's on the state to take care of the storage side of the equation.
Or switch some of the incentives to distributed storage as was as distributed generation. It's less efficient than large scale storage, but means we all have to depend on the grid less.
For example, in Vermont the utility will sell you an extremely discounted Tesla battery, because the most expensive electricity they buy is during times of peak demand, so if you have a battery they can buy less of it.
https://greenmountainpower.com/rebates-programs/home-energy-storage/powerwall/
I think that culturally, we need to accept that solar is saturated and batteries are where it’s at.
In California, there are regulations for new construction. It seems there’s a minimum requirement for the amount of solar power and also, they need to be “ready” for energy storage. Maybe the solar panel requirement should be scaled back to a “ready” requirement?
This sort of thing makes housing more expensive, so it’s important not to overdo it.
Batteries aren't quite where it's at - load shifting is where it's at. So for instance, being able to use AC to store heat/cold during peak, then tap into it during off-peak. Or basically turning any time-sensitive appliance into one that's not time-sensitive, even if it's less efficient as a result.
Yeah, that too. I was thinking more along the lines of home owners wanting to do some kind of upgrade to be more green. Solar is the first thing people think of.
Load shifting and local energy storage are both ways of reducing the need to upgrade the grid. Batteries also help for outages. In some areas, power companies are cutting power more often to avoid wildfire risk.
Perhaps in some states, but not in all. Besides, if the US keeps pursuing electrification, the demand will continue to increase, which is a problem that batteries can ameliorate but not solve. Today, do we have enough locally produced electricity to meet the peak demand that exceeds transmission capacity in a decade or five years?
If so, I would say that we should do as you suggest and level out solar power production and focus on improving storage. If not, though, then ramping up solar installations are a great way to ensure that the supply and transmission capacity are expanding to meet future demand.
Things are going to get uncomfortably hot and people will depend on electrically driven mechanical heat pumps for cooling. If that fails, the health and safety of many will be in jeopardy. For some, I predict that having electricity will be a matter of survival.
What do you think?
Prices for solar panels have mostly been going down for a long time. Planning ahead for anticipated demand makes sense, but maybe not actually buying them yet, if the demand isn’t there?
In thinking about your comment, I came to agree with it more and more. We just got approved for a lower rate at off peak levels because we have a plug in hybrid. Right now, we have net metering and solar, so we don't benefit from additional storage. As long as watts of net consumption come in at night, we pay half price.
Residential rooftop solar is expensive and difficult to install, but residential batteries are much more amenable. With batteries, I could buy and hold electricity only when it is cheap. But more to the problem of the duck curve, the utility can just incentivise purchasing energy during excess production and at night, when demand would normally be low.
Incentivising residential battery purchase with lower time of use prices would ameliorate a lot of the demand curve problems with solar without making utilities install capacity.
It seems like somewhere in the middle is most desirable. Continuing to provide incentives to build is probably a good idea, but reducing compensation for excess energy to the market rate also makes sense. Utility companies need to get some non-chemical batteries in place and there should be as much solar as possible to fill them when they're ready
On the opposite side of that, my state just started pushing Solar. I got panels and supposed to be locked to 1kwh to 1kwh net metering. So if we ever reach those levels, my house should be exempt to any reductions.
Year to year though my house evens out in terms of solar generation & usage. Having all four season will do that for you.
This is part of a "sea change" for utilities. They are in the process of changing from energy providers to energy regulators/managers. Many utility companies have been fighting this change tooth-and-nail every step of the way. Others are trying, but it's a tricky, complicated change to a business model that hasn't seen innovation in, IDK, a century or more.
California is, I think, better, more innovative, more accepting of these changes. This article is mainly just talking about rooftop solar gaining popularity faster than the utilities anticipated, and so now there is often excess client power that they don't know what to do with; it's an issue that they will work out, but it'll take years for them to adjust their central production and storage plans, to meet the faster-than-expected rate of change.
Several years ago, there was a huge legal battle in Hawaii about the utility providers not wanting to pay fair market prices for the electricity flowing into their grids from solar-electric client homes, and even blocking solar-electric clients from feeding their excess into the grid, forcing homeowners to either set up battery back-ups and/or throw away their excess electricity. The utility provider(s) had some legitimate issues relating to the difficulty and risk to the entire grid, from allowing individual homes to feed current into the grid ... but as I recall, they were using that as an excuse to try to maintain their monopoly on electricity.
This is also where the rise of micro-grids is coming into play ... communities -- sometimes quite small, just a few dozen, or even a handful of homes -- communally purchasing large, common-use battery back-up systems to feed their electricity into and then tap into during high-use, low-generation periods.
Ultimately, I think a larger version of that community-based model is the future of electricity, with a kind of Internet of microgrids, and the utilities more and more existing to manage and maintain the lines and the local back-up systems, and less and less, to actually create power to sell, except as a kind of emergency provider of last resort.
Of course, people will still have to pay them for those maintenance, management and--effectively--power-insurance services ... but in a perfect world, those fees should be a tiny fraction of the cost of actually buying power from them.
That might be the future in places like California and Hawaii. But in large parts of the word, this won't really work.
Many people live in places where winter has persistent cloud cover, and wind is unreliable. There's to many days, where the wind is not blowing after an overcast day of diffuse winter sun on your panels has left your batteries empty.
During those days, a community like this will need to import so close to 100% of its energy, you save nothing by having a microgrid in the first place. You still need all of the macrogrid anyway.
I'd advocate expanding the macrogrid instead. California and Arizona have their worst "duck curves" in spring, before everybody there turns on the AC. Luckily, this is right when the northern states still have lots of overcast days with low incidence sun light. So don't have the microgrids throw electricity away, sell it up north instead. Just needs a couple of new HVDC transmission lines.
You're right it can't replace larger systems everywhere. But solar is not just getting cheaper; it's also getting better at generating energy under less-than-ideal circumstances.
Also, it really is a pretty unusual region that gets neither sun nor wind for long periods of time. While it's certainly not universal, the two do tend to be complementary, and regional wind farms--perhaps managed by those very same utility companies--will go a long way towards supplementing smaller local grids.
Future-forward, the best thing commercial utilities could be doing both for themselves and for the future of humanity, is developing and building cheap, reliable, long-term energy-storage systems ... non-battery systems like the pumped-water, sand-ballast, and molten-salt reservoirs ... that can store energy for weeks or months.
What do you count as a long time, and how much must production fall for it to be problematic? You'll find some data on frequencies of these type of events for north and baltic sea countries in Li et al. I have not had time to even skim it properly, but figure 3 on page 5 illustrates frequency of events for Germany, Norway, and the UK, based on capacity factor and duration of event in days.
Events lasting 3+ days at 20% or less capacity of solar PV and wind happened on average every few years in each of them (somewhere between 0.2 and 1 occurrence per year).
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Enhanced geothermal systems could supply consistent energy in cases where traditional wind and solar can only take part of the demand. Newer geothermal technology doesn't need to exist everywhere or cover 100% of electricity use; it just needs to cover the generation gap between solar+wind real capacity and consumer demand.
With those three sources in tandem, the amount of long-term energy storage required (sand batteries, etc.) for a community becomes relatively small. Not nothing, but far more feasible.
It is also worth noting that solar cell efficiency has increased over time, both in laboratory settings and in consumer-available products. New types of solar cells, such as perovskites, now have higher theoretical efficiencies than silicon cells. (They aren't expensive either. In this case, the work that remains to be done mostly has to do with extending the lifetime of the cells.)
Likewise, wind turbines are constantly changing. Efficiency improvements so far have largely come from larger wingspans, which has its limits, but simulation research indicates that slight modifications to the curvature of the blades to resemble condor wings could result in a 10% boost to efficiency. This new design requires no more space than current ones.
Thus current production gaps from solar and wind can be expected to decrease as the technology improves. And unlike some other kinds of technology, both of these areas are promising (especially solar).
Transmission infrastructure is always going to be necessary in some capacity to maintain a healthy grid during extreme localized weather events and other catastrophes, but I think it's quite safe to say that moving toward a semi-decentralized model using renewables is both feasible and worthwhile.
Broadly speaking I agree with your conclusion, at least to the extent that it should be seriously considered as a possible approach. I am definitely not up-to-date enough with the state of the tech to contribute much to any informed discussion here. My comment was made in good faith, objecting specifically to the quoted section, as my experience is that I seem to hear reports of it most winters. My question wasn't rhetorical, because I honestly don't know the answer to it.
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It was a good comment and you’re asking a good question. The answer is ultimately not a matter of percentages but of cost of implementation, which is location-specific in much the way nameplate capacity is.
I’m also kind of speaking about the future in a vague way and not right now (because right now, the generation gap is immense).
There are economic and political reasons that some tech will be employed in some area—not just its theoretical efficiency. And in some places there may even be greater perceived or actual value in overbuilding renewable infrastructure to account for rogue efficiency drops, even if that means a certain amount of idle equipment.
As a point of comparison, civil engineers design structures to withstand theoretical “100-year events” (or 200, or 50, or 10000…) based on the value of the structure relative to the cost/risk of various solutions. In these cases the issue isn’t that they can’t build a dam a thousand feet high, it’s that an actuarial table tells them not to. But they could, if sufficiently motivated, ignore such a table (in either direction).
The other thing I neglected to mention is nuclear power, which is admittedly hard to modularize (though people are attempting). A place like Germany has willingly chosen not to invest in nuclear energy for political reasons mostly, and thus has shot itself in the foot as far as “renewable stability” is concerned. Like most problems, we create them ourselves.
Very long-term (end of the century), there will very likely be a viable method of generating electricity using fusion. We are already decently far along. That’s not really a climate change solution though. Too far out.
Just on the topic of Perovskites, there's one company (Verde) I've seen so far that looks close to commercial deployment of Perovskite panels. This is a big leap from a few years ago where rapid cell degradation (short cell life) was the biggest limiter on commercial scale up. So perovskite panels as a product is looking extremely close to reality!
https://www.verde-technologies.com/
It's also worth noting that you can't just set up wind power anywhere either, so I'm skeptical that even when wind can help compensate for poor conditions for solar, it won't be suitable for at least a large fraction of such microgrids.
There's been new innovations in urban wind generation that take advantage of the choppy urban breeze and building design that might do a good bit to make it more effective in the next 3-5 years.
More effective is good, but is it ever going to match having dedicated wind farms in the most suitable places?
If an area doesn't have the kind of wind that those wind farms need, are they really the most suitable for the situation?
...I don't really understand what you're saying. The idea is that it may be better (more efficient and such) to have wind farms in areas that are suitable as part of a larger macrogrid rather than relying on less efficient urban wind power as part of a local microgrid.
Right, but there are large areas of the world that don't have those sorts of places. At some point the cost for the transmission infrastructure starts to drag down the efficiency of the larger wind turbines. Trading absolute efficiency in an inefficient location for lower efficiency at the location of energy consumption can be a reasonable tradeoff.
I'm having trouble understanding what (if anything) we're disagreeing on. The statistics you just cited sound great to me. Having to pull in power from an outside source once a year or less sounds like a great set-up, especially if the opportunity arises to feed into that outside source on the days your local system is running over capacity.
The part my intuition objects to is specifically the section of your reply which I quoted, regarding describing the regions as unusual. That's why I quoted it, to provide context of what I was commenting on.
A situation that leads to 80% power loss over several days on a country wide basis, particularly in winter months in colder climates, certainly seems a significant impact to me and something a microgrid would find hard to just "pull in" from outside sources (unless that is a very large grid). Finding supporting data that it happens on a near enough yearly basis with events lasting several days in countries around the north and Baltic sea makes me consider these events as not that unusual, but that is definitely a matter of opinion. Admittedly, for the limited amount of time I spent looking for data I didn't find any summary for other regions, so while I doubt it, it could very well be basically unheard of in the rest of the world.
That is to say, to me it seems as if dismissing the low-solar low-wind events as unusual isn't helpful. We should try to quantify it in different regions and dimension our systems to account for it. This includes diversification of renewable power sources to reduce intermittent power loss, as well as energy storage and transfer capacity to manage the remaining risk.
I don't think so. Once you go a few miles inland, that's most of continental Europe, the Pacific Northwest or the Northeastern United States. And even if you have a pretty good spot for wind power, you're still screwed if there's even only 1 week of low winds in winter or spring. Which happens frequently, even in spots that have perfect wind 300 days a year. Because on the micro-grid level, storing power for a week is completely non-trivial.
I think the current consensus is that once you go towards weeks or months (multi-TWh storage with multi-GW output), hydrogen is really the only game in town. At least once you take into account basic economic factors and constraints like actually available land for pumped hydro.
Relevant condensed graph:
https://www.reddit.com/r/dataisbeautiful/comments/17r9q6s/oc_most_costcompetitive_technologies_for_energy/
The source has much more detail, not animated:
https://www.storage-lab.com/levelized-cost-of-storage
Can confirm. Living in New Jersey. While wind is readily available where I live, it's tricky to deploy as a homeowner unless you have a very large ( > 1/2 acre) amount of land to comply with zoning codes.
And we just came off of like 2 weeks of "mostly cloudy with mild winds," along with a surprisingly long, cool spring. Like we just had a fluke frost drop 2 days ago.
Expanding the macrogrid is politically hard because when expanded past state lines it's definitionally interstate commerce and thus can be federally
sabotagedregulated. Basically, California doesn't want any of their grid to be regulated by Trump if he wins 2024.There are ways to mitigate this and expand the grid across state boundaries anyway (and this is being done), but it's not the freebie it looks like.
Mirror, for those hit by the paywall:
https://archive.ph/jCrJx
Someone please enlighten me: Why cut down incentives for rooftop solar, instead of selling that excess energy elsewhere? e.g. to another state.
The grid can only handle so much electricity at any given moment (especially since it was designed historically for one-way flow: generation -> transmission -> distribution -> consumption). Additionally, you’d need to increase it to higher voltages (and possibly different currents) to prevent excessive transmission losses. For example, the Pacific AC Intertie that runs from Oregon to Southern California is at 500 kV. The power lines that deliver electricity to the transformer, and ultimately your home (at least in NA) are at around 12.5 kV.
Alternatively, why not store that excess? Why toss it away?
Storing electricity is hard. There are various ways to do it, but they tend to be expensive, and often location-dependent (for example, a hydro battery that stores energy by using it to pump water into a high place, and provides energy by letting that water fall back down again).
There are lots of improvements in this area happening right now, so hopefully in the future it'll be easier to say "oh, just put it in a battery", but right now that's not really feasible, at least not in the sort of bulk that is useful to large-scale national grids.
Batteries are expensive, and complicate installing rooftop solar. Some of the most popular systems are battery-less grid-tied ones.
I am a Californian (well, I was born there and it almost took three decades to get out) who works in the power generation industry (not in CA, and I work with fossil fuels), and this topic plus this thread really has my hackles up but I completely understand the goal. Once again, I feel the need to explain (but won't) that we're not on target to fully go battery, because that's what our technology needs to hit. My company has some carbon capture options in the plans, but my own site's battery setup has been shot down twice now by NIMBYs.
Everyone wants to change the world, but no one wants to change themselves.
The problem is fundamentally one of infrastructure investment, or lack thereof. Ideally it could be sold to neighbouring states, but the grid is old and can only handle so much power exporting.
I think sand batteries could be a really interesting way of storing extra electricity in an environmentally friendly way. Downside is that it's only being used for heating water for warming buildings, rather than for generic electricity usage
https://www.euronews.com/green/2024/03/10/sand-batteries-could-be-key-breakthrough-in-storing-solar-and-wind-energy-year-round
I see batteries as a possibly easier and more resilient alternative to upgrading the grid.
In the short-medium term? Maybe, but our electricity needs are only going to keep increasing as our transport moves away from petrol.
In the long-term, I think some combination of renewable, batteries and nuclear with better power-sharing would be the end-goal. Nuclear, wind and batteries could provide the overnight power, while during the day the surplus from adding in solar could recharge the batteries and be sold to other locations.
I'm not sure why we're so allergic to long-term planning these days, infrastructure like the London sewer system were built to last a century (and have well exceeded that). Considering we're living in the richest time of human history, with the best technology and most educated engineers, it makes no sense to scrimp on infrastructure.
It's been shown in that access to reliable energy is one of the key resources that contributes to future prosperity.
Sure, the grid will probably need upgrading too. But maybe we could also do whatever we can to use the grid capacity we have more efficiently? Maybe batteries are part of that?
More generally, modern economies are built on cutting costs. For example, what is increased productivity? That's about reducing the labor needed to produce the same stuff.
Also, if we can somehow figure out how to build infrastructure for less, we can build more of it.
You're totally right about using what we have more efficiently.
However I'm always a little wary of trying to cut costs with something as important as infrastructure. The incentives need to be carefully chosen to avoid long-term failures.
For example, having private companies responsible for infrastructure (whose goal is to be efficient at making money) is what caused disasters like the California wildfires from the worn-out hook on the transmission line. They deemed it more profitable to fix it after the fact rather than pro-actively upgrade it.
It’s a complicated situation and I don’t think the lesson is necessarily “the government could do it better.” Electricity generation is highly regulated. In order to spend money (enough so they need to raise rates), PG&E needs to get approval from the California Public Utilities Commission.
In some ways, this doesn’t seem all that different from spending taxpayer money directly. Raising electricity rates is politically unpopular, like raising taxes. It’s governed by a political process. There’s no guarantee that it would go any better under direct government control than it did under indirect government control. Maintenance could still be underfunded by governments to avoid politically unpopular tax or rate increases.
One difference is that there are more forms of financing available. A government raises money by selling bonds, but a government-regulated monopoly can also sell stock. When something goes very wrong, the stockholders lose their money first, as happens when PG&E goes bankrupt. (Twice so far.)
With direct government financing, all the damages would have to be paid by taxpayers. (Unless the government itself goes bankrupt, and then bondholders would lose.)
Also, we can think of PG&E as being a politically useful scapegoat for government mistakes. If it were government controlled, elected government officials would take the full blame, but after electing new officials, then what do you do? The mess is still there.
I think local governments having their own power companies (like Alameda does) might help for some things. Alameda’s power company seems pretty low-drama. But it wouldn’t help maintain a network of large power lines through rural areas.
Looking at PG&E's net profits over the decade prior to the 2019 fire (many hundreds of millions per year), there'd have to be a very good reason why they didn't have enough money to invest in the infrastructure.
https://www.macrotrends.net/stocks/charts/PCG/pacific-gas-electric/net-income
Additionally, while spending on infrastructure would be expensive, as Last week tonight explains, it would actually bring a lot of well-paying jobs to the central states.
https://youtu.be/qBpiXcyB7wU
I agree that just having it be government controlled isn't a cure-all, but the incentives are at least better aligned - yes, you don't want to increase taxes, but you definitely don't want to be the party in power when it fails. Meanwhile even if PG&E goes bankrupt, the executives can walk away with a golden parachute and never need to work again.
I've got a little bit of insight into PG&E, and one perspective is that PG&E's CEO is basically a revolving door scapegoat. They get a new one every 3-5 years because each one steps down when the newest problem happens. San Bruno major gas explosion, new CEO. Paradise Fire due to maintenance neglect, new CEO. The vice presidents are much more stable and have more direct influence over operations, and they don't get canned when something goes wrong. So the CEO might get a golden parachute, but it's because they know they're going to get the axe as soon as something goes wrong.
Is this how things should be run? Absolutely not.
Assuming what they did is a mistake rather than being criminal, both politicians and corporate executives can walk away from disasters. I don’t see a big difference.
This is particularly true if the consequences happen after you’re gone.
Hawai'i, or at least a couple of the islands, might be a good example of achieving what you're saying. There's a recent article on the subject of incentivizing home owners to install batteries and to specifically mandate that those people who are part of this program allow the power grid to pull from those batteries at high demand periods (6:00PM-8:30PM). In exchange they get a pretty good payout, plus a monthly payment from the power company.
There are some challenges to making this work in other locales, and I'm not familiar enough with population density and energy demand to make any comparisons. But I would be concerned that the examples of Maui and Oahu make this difficult to justify for a few reasons:
Population density in California is a lot different than Oahu or Maui. Maybe that works for the best for rooftop solar and energy distribution, maybe it poses transmission/infrastructure problems. Similar to the Hawai'ian islands, rooftop solar is primarily accessible to wealthier people and therefore wealthier neighborhoods. You can get situations where entire neighborhoods are plastered with solar, and might be substantially benefiting from battery backups, but those pockets of self-sustainability (and even net-positive generation) aren't able to transmit a meaningful amount of electricity to what are essentially lower-income neighborhoods where population density is higher.
A lot of home battery systems are either lead-acid or lithium-ion. I'm not sure either of those are really good short-term solutions at a consumer scale when it comes to energy independence (or grid supply by homeowners), environmental sustainability, or long-term cost effectiveness. It's yet another way for power (transmission) companies to offset their own costs by incentivizing a few people and kicking the can down the road.
Incentive dollars are at a premium, especially while businesses (and lobbyists) are fighting solar expansion. People who are financially capable of taking advantage of those incentives will benefit disproportionately (which in a perfect world isn't a problem by itself). In Hawai'i, rooftop solar is largely out of reach of lower-income households and while there are programs to make rooftop solar more affordable to those families, I would bet that much more money is being spent on incentivizing things that are only accessible to higher-income/higher-net-worth homes, than creating a more equitable energy self-sufficiency. Some of that will be sorted out as equipment costs come down, but that's a long-term thing. As mentioned by others, if there isn't enough transmission capacity (and efficiency) in the grid to supply those lower-income areas, then they get brown-outs or black-outs while higher-income neighborhoods have insulated themselves with tax dollars incentivizing balanced usage, rather than reducing consumption.
That's all I can think of off the top of my head. But I think there are solutions to all of those things. And I do hope that sand batteries take off as a technology because that is really cool and probably the great idea in practice that it seems to be in limited experiments.
Yes, interesting example. A Vermont utility is going to be doing something similar, but with batteries provided and controlled by the power company. This might be a way to get them installed in rural areas.
I think anything reducing demand on the grid is beneficial to the people still using the grid, in a similar way to how people who don't drive aren't contributing to traffic. This is still true if the people who don't drive are wealthy.
However, it can be a problem if they aren't paying for electricity, because it reduces revenue for the power company. It seems California might change its rates to charge for being connected to the grid as well as a price for electricity (which will be lower).