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The thing we should be incentivizing people to use here are batteries, in the exact same configuration. We do not in many places, need more solar power generation, but we need devices that slurp down power at 2pm and dump it out in the three hours after sundown. Utilities should be paying anyone who dumps power to the grid at peak post-sundown demand hours, so that it is a no-brainer to install such a thing.
At least in the US, no, for one simple reason: grids in the US rarely to never have an excess amount of renewable generation capacity.
In my area natural gas is a consistent 40-60% of generated power, with solar rarely reaching more than about 30-35% at high noon in the summer.
Right now (as in at this very minute, high noon) in CA ~70% of the power being generated is renewable. That's 30% that could be solar, and isn't.
When there's excess renewable generation capacity (or about to be), sure, let's talk about installations for storing it.
In the meantime utilities are deploying battery systems for virtual grid inertia, to avoid having to use "peaker" plants, reliability when transmission lines go down, and for transmission line maintenance.
That might have to do with existing deal structures to maintain a non-renewable base load. Something like, if cloud cover/wind suddenly changes, we want to ensure there is already X% of natural gas running so there is a less sudden surge. There is a lot behind the scenes planning to try and ensure grid robustness.
California is certainly curtailing a lot of energy. EIA report[0] said 3.4 TWh in 2024, which was a 29% increase over 2023. If I am reading this[1] chart correctly, the 2024 California demand was ~275TWh.
CASIO also has pages dedicated to curtailment with much of the data available[2].
[0] https://www.eia.gov/todayinenergy/detail.php?id=65364
[1] PDF https://www.energy.ca.gov/sites/default/files/2024-11/2024_C...
[2] https://www.caiso.com/about/our-business/managing-the-evolvi...
California has huge amounts of excess renewable generation nearly every day, especially in spring and fall. Last April the grid operator curtailed 1.47 million MW/hrs of renewables, or about 2 GW per day. That's excess power the grid did not accept due to no demand. (source: https://www.caiso.com/documents/key-statistics-jul-2026.pdf)
In my mind the ideal solution is in addition to daily BESS time-shifting is seasonal time-shifting: long term storage of April excess for use in July.
Generators don't ramp up/down immediately. Especially when peak power usage is 4-5pm, people getting off work, but also closer to sunset. That's a lot of power that needs to be generated immediately for stability.
More solar (without batteries) makes that worse.
A suggestion I liked was to time-shift water heaters as a thermal battery. Water heaters are a significant sink (~20%) of household energy. They are already installed and well insulated, you just want to over-heat them during cheap noon solar to off-set the heat losses over the day.
This is basically how solar hot water heaters work today (I have one). They are superheated during the day (75C/170F) with a mixing valve to produce warm, but not scalding, water to the tap. The tanks are also oversized with a backup electric heater for the top half of the tank.
It works pretty well for my climate. I wonder how it compares to PV panels driving an electric heater though. Neither is going to work very well during the winter but the hydronic based system probably needs to get above some base level of solar input to meaningfully heat the water. Whereas PV will always produce some electricity in the winter which can always be converted to heat.
this seems like it makes sense. how do you keep the dispensed water from being too hot? is there such a mechanism?
I'm getting a battery soon so I can get paid £1/kWh to dump power at specific times with axle energy https://vpp.axle.energy/landing
Don't expect that to last. £1 per kWh = £1000 per MWh. Even when things went crazy as sanctions kicked in and Russia were attempting Blitzkrieg in Ukraine the wholesale prices never hit £1000 per MWh.
They say £1/kWh is a Beta price, that makes sense as a way to burn investor money to get people interested. Their real price is TBD. Would you take 25p per kWh with a £5 per month guarantee ? That could be at least in the ballpark of working.
Be careful with these kind of long term sell back agreements.
In the USA lots of early adopters of solar did so under net metering agreements where excess electricity is sold back at full price. After a number of years it was costing the utility companies too much money. So they updated the terms such that residents with solar buy electricity at retail prices (~$0.25) but sell it back at wholesale (~$0.04).
> batteries
Not exclusively. A few power companies (like SRP) innovated here with TOU plans that have variable costs throughout the day. You can save huge amounts of monthly spend by moving energy intensive work to off-peak hours and by “priming” things ahead of peak hours, like over-cooling your house ahead of the peak window.
The most costly part of an infrastructure build out is supporting peak-of-peak - that capacity exists year round to service the demand generated by peak mid-day usage during a heatwave in July.
If you can “lop off” that peak - it dramatically reduces the infra build out cost.
Peak-of-peak tends to correspond with sunny days: mid-day in summer. I could see battery-less solar being a useful tool there.
related tangent: install costs of batteries and solar in California are insane. I recently had battery and solar installed, and labor and permitting were 60% the cost of the system. Systems without either of those markedly bring down the cost.
The biggest obstacle to solar in the US: utility companies.
Ask anyone who has had a system installed. Your system can be totally compliant with national and state electrical code, installed by a competent installer using staff who are licensed electricians, get a stamp of approval from your own's inspectors - and the utility will refuse to connect it and insist you meet an additional set of their own conditions.
And there's nothing you can do about it. No appeals, no review process, nothing.
It's not even consistent, with utilities seeming to just obstruct for the sake of obstructing. Over and over I've of systems going in, the utility comes out (eventually) to inspect, refuses to connect. They're called back out, nothing has changed, and the system gets approved.
This is legislatures getting tired of all that power company bullshit, and bypassing them. As balcony solar rules hit state legislatures, expect some really absurd scare campaigns by power companies, and lots of lobbying.
Power companies see every solar panel they don't own as a threat to the profits they make on their fossil fuel power plants.
> Ask anyone who has had a system installed. Your system can be totally compliant with national and state electrical code, installed by a competent installer using staff who are licensed electricians, get a stamp of approval from your own's inspectors - and the utility will refuse to connect it and insist you meet an additional set of their own conditions.
Well, I am someone who had a system installed… I have a 14000 KwH per year system, and two 13 KwH batteries. It did take a while to get it inspected, which was annoying, although I was able to use it while I waited (I just couldn’t sent power to the power company until after), but they approved it the first time without any additional requirements.
What makes you so sure everyone has the experience you are talking about?
Yeah the truth is much closer to your experience than OP but, especially in California, there is a non-zero amount of people passing inspection but waiting a long time for the poco to give approval. Most delays don’t seem to be related to additional requirements but rather the poco just dragging its feet…
A single counter example: In East Bay CA. I designed and built my 9kw solar roof installation myself. No electricians at all. The process was very easy and working with my city and power company was simple, with no blockers at all. 4 years running. On a yearly basis, we make over double what we use. It boggles my mind how solar isn't on every house in the country.
It should be noted that if you are willing to forego selling excess solar power back to the grid you can bypass the need for inspection or approval from your utility.
Put some (or all) of your circuits on a transfer switch or generator interlock and connect your solar system to that.
Then legally your system is the same as a backup generator install. It should have permitting and inspection requirements similar to those of adding a circuit. That will just a city permit and a city inspection.
> Ask anyone who has had a system installed.
This didn't happen to me or anyone else I know with rooftop solar in multiple states, and I've never heard of it. What citations do you have?
You could do what I did and set up a zero net export system and just not tell the utility.
This is going to be made legal in the UK on the 27th August. Max 800w inspired by Germany. I'll definitely get some panels and see how they go.
To be precise (Germany): 800W inverter, 2kWp solar panels (maximum 4 panels). This allows you to get the 800W during long periods of daylight (e.g. east/west configuration). You only need to add the installation to a public database and plug in the inverter.
Before it was more complex (special plug needed, only 600W, need allowance from grid operator) and still we have ~1.5 GW installed plug-in solar plants. It's almost always a no-brainer, RoI is typically 3-4 years while the lifespan is 20 years.
Edit: My state had a subsidy of 300€ when I bought mine, so the RoI was instant ;-)
They're a no brainer especially if Lidl can nock them out for around £200 in the centre aisle.
Unfortunately for me my back garden has too much shade for panels and I don't think I could get away with them in the front.
So that leaves a roof top install and I think once you have scaffold that you might as well have a traditional install.
I have a two panel system, and the panels are about 430 watts each. Given the current ToD rates for electric, it will take years to pay back.
Microinverter: 400 Panels (used): 250 for both Cables: 50
I also picked up two LiFePo4 batteries and two Kasa smart plugs and time shifted my computing infrastructure's electricity usage. That made much more of a difference in my bill, since a few hundred watts moved to .09/kwh. If the bms was smarter i could charge the batteries with solar, but alas i can't cap the recharge current.
Let's just point out that it isn't about the line workers, it is about raising prices on consumers.
They'll replace the line worker at the drop of a hat, and fight tooth and nail to grow profits, that's just how corporations work.
Which are the high quality chinese brands of plug-in panels?
I've seen Ecoflow mentioned on YouTube but I don't know how reliable that is.
Anyone have good suggestions for stands for 2-4 panels?
One thing I've read is that if you can dual sided panels mounted on a frame over white gravel and really boost secondary feed as much as 20 to 30%.
If they're mounted on a roof then obviously you can't benefit from that so it would be cheaper to go with single sided panels.
This is in my opinion a bad solution to the problem of expensive energy or renewable transition. Having individuals start managing their power via plugin solar and plugin batteries creates a gap between the people who can afford it and those who cant. The people who cant afford it end up paying more for electricity.
A better solution is to do this on a local or federal government level and build the required amount of power.
Energy is expensive due because demand exceeds supply. Individuals generating their own energy are increasing supply.
This is different from net metering at retail rates, which arguably does move costs from richer ratepayers to poorer ones.
I dont understand it. If most grid capacity is already installed, the people who don't build their own little island with solar and batteries end up being shrinking demand against a pool of fixed supply. Meaning their bills probably decrease.
There is the hiccup of universal distribution which needs regular maintenance, and is separate from electrical supply. But if this is remediated by charging solar owners base fees/connection fees, or if grid maintenance is only minority portion of electric utility bills (in the US it's about 40% with electricity production being 60%), the direction should still be poorer people proportionally benefitting.
You basically kill any momentum of that happening in any reasonable timeframe the minute you said government.
In Australia there’s a ridiculous amount of household solar & now battery being installed. Despite all the attempts by companies/governments to do something, they just keep getting in the way of themselves.
I’m glad the option exists for people to go their own, that of course puts the bar at the individuals finances.
Plugin solar is really cheap though. It's possible the price of an 800W kit drops to $200. That's really not a lot for something that could pay for itself in a year and keep saving you money for years to come.
Then there's the prospect of the price dropping even lower in the next few years. Imagine 800w kits for $100. How can you ignore something like that?
If demand decreases then that can cause energy to become cheaper.
How would this make it more expensive for people who can't?
There was a carport fire in my building back in the 90's. The firefighters got all set up to turn their hoses on it but did not actually start using water to fight the fire until the utility guy from the city arrived to de-energize the supply from a nearby vault.
How does that safety protocol work when the electrical connections and supplies are distributed around the house and may be inaccessible due to fire?
In Germany, where this kind of plug-in solar panels is very common (1.5 GW installed power) it is mandatory that the inverter powers itself down as soon as the grid is offline/disconnected. It has to be so fast that you can savely touch the plug after unplugging it.
I guess it's standard everywhere.
I imagine the solar panel will detect when the circuit it is plugged in to is de-energised and stop supplying supplemental power to it.
companies that sell plug-in systems argue that safety risks are minimal or nonexistent. Mr. Scherer of Craftstrom said his company’s systems would not shock electrical workers because they shut off automatically within one second of a power disruption or grid outage.
Mr. Boyce of UL Solutions said his company would certify panels only if they did not pose a risk to consumers or utility workers.
Maybe the fact that these panels are legal around the world and soon will be legal in a number of US states should be a sign to you that this is not a relevant concern.
The device looks for an existing signal from the grid, and if it doesn't find it, it stops feeding power. It even waits for 3-5 minutes before trying again plus some random jitter to avoid thundering herd. It's been a standard in Europe for a while and now finally in the US. This of course depends on the utility and state as not all of them have adopted it but it's quickly becoming the standard everywhere.
IEEE 1547 (interconnection behavior), UL 1741 (inverter product safety), UL 3700 (plug-in solar). (also there are newer revisions you need of some standards like UL 1741)
This is absolutely insane. This is the most inefficient way imaginable to deploy solar power.
We could deploy 100x the capacity $/Wh with utility-scale farms. Unfortunately we are just completely failing on basic coordination problems like this in the west, every man for himself.
It is inefficient in the grand scheme of things yes. But it is very efficient on the level of the individual home owner, especially if they do not own the building so cannot install solar. It is a good way to cheaply reduce the cost of electricity.
Yes, installing the solar power globally, and getting a globally connected grid would be more efficient in terms of solar panels/kW(h). But alas, that also requires a lot more infrastructure.
In the mean time this can reduce the energy bill for many people. Especially, if tied to a battery. It is not intended to provide independence, for that you need a lot more capacity.
People buying panels with their own money doesn't take away dollars from utility solar.
Nothing about this prevents utility solar