Heyo everyone, cool to see this here. I'm a co-founder and head of product at Grid Status if anyone has specific questions about the site. I see some energy market questions here about CAISO and natural gas, net load, etc., so here's a link to a blog we wrote last year that covers some of these topics, might be helpful[0]. The market has been setting a bunch of records recently, which you can see here[1].
Also, as a bonus, if you click this link[2] while logged in it will enable a preview of our nodal price map app which people tend to enjoy playing around with.
The fun bit here, for those who missed it, is the spot price being negative - ie there's so much solar being generated that industrial consumers are being paid to consume electricity!
It's interesting how renewables have suddenly made time-of-day critical in energy consumption.
IMHO, not enough attention has been paid to how important better insulation + workplace EV charging are to the energy transition. If homes were insulated like they are in Northern Europe (where you can go a week without heat and your home will still be tolerable when you get home) rather than Northern California (where your furnace cycles on after an hour despite it being 55F out), you could run basically all residential HVAC during daylight hours, when solar is producing abundantly, and turn the housing stock into a giant thermal battery. And similarly, if everybody charged at work rather than at night, you power transportation on solar rather than on natural gas.
If consumers paid close to wholesale rates for their home energy they would be highly incentivized to do these sorts of things: they'd pay almost nothing (or maybe even less than nothing) in the day and big bucks from 5 PM to 8 PM. There would be whole industries helping people shift consumption to daylight hours. Unfortunately legislatures have consistently been acting to shield consumers from variable time of day costs, preventing behavior adjustment.
It's nowhere near the price differential that wholesale is, though. Last I checked, PG&E charged 62c/kwh at peak, and 52c/kwh off-peak. Back in 2020 it was 29c/kwh peak and 22c/kwh off-peak. That's roughly a 25% difference, but the actual wholesale price is off by several factors.
Well yeah because most people are away from home during those hours so there's little you can do. And workplaces, schools like that working hours are when electricity is cheap.
Workers might start demanding WFH or that their leisure hours be during the day and we can't have that.
The point is to enable markets for the technologies (many existing today!) that would let you time-shift effectively. Smart lights and smart thermostats are nifty gimmicks today; if electricity cost 100x more at primetime, they'd become critical investments. Insulating and air-sealing your home is known technology, but often not cost-effective when you can just burn a little more natural gas. Workplace charging is a perk, not a deciding factor for where people choose to accept a job. If the consequences of people's decisions were priced into the cost of them, people might make different decisions.
I'm not sure smart things and sealing would be the go-to solution when we're talking 100x the cost. Even 10x the cost starts to make the electricity bill close to rent. Whole house batteries, gas/pellet heaters, and gas stoves would suddenly get a lot more popular.
I'm not sure "throw out your major appliances that run on electricity and don't even look at plug-in EVs" is the direction we want to go when being able to cheaply meet evening demand at the grid level with renewables is the eventual goal.
The 100x comes from it being way cheaper during off-peak, not way more expensive during peak. You see the wholesale rates on this site; they're negative or a few cents/kwh at most. If that price differential were translated to retail we'd see rates of ~1c/kwh off-peak and ~$1/kwh peak, which is a pretty strong reason to charge your EV off-peak.
I don't understand why the government don't do more to support these kind of tariffs that incentive demand shifting.. it seems such a powerful way to make the grid greener without huge infrastructure projects
They're very unpopular with consumers, who are allergic to price increases and particularly to variable price increases. Look at the blowback to Wendy's surge pricing on burgers, or to Uber surge pricing, or to toilet paper scalpers in COVID, or to any notion that you might lose your job and need to retrain in a different one in response to changes in the economy.
The last thing a politician wants to do is lose an election, and losing an election is usually what happens when you suggest that the electorate bear the consequences of their behavior. As a result, we usually drive straight off a cliff, have a war or societal collapse, and then whoever survives it can go build a new system out of the rubble.
There are gobs of fascinating battery ideas like this! Pumping water uphill, heating up enormous piles of insulated carbon, spinning monstrous flywheels, etc. Their plausibility is highly dependent on the environment. So I hope that we'll eventually have a constellation of these wild batteries supplying the world's storage needs. I suspect that we'll see the idea you described gain more adoption. The result: fleets of "air battery" homes climate controlled by municipalities via opt-in smart thermostats (and credit incentives) to ease grid loads.
At a previous job I helped build a hyper local method of computing spot prices to enable lots of cool ideas. We could compute unbalanced prices on the distribution grid and had a pilot project where DERs were priced based on how the influenced the local distribution grid.
For example, placing solar downstream of a transformer nearly at capacity could allow for deferral of capital upgrades that would only be needed for a few hours a day.
> It's interesting how renewables have suddenly made time-of-day critical in energy consumption.
I remember people being upset about potential time of use meters around 2000. Of course then we wanted to move consumption away from daytime when peak loads were higher than supply. Now we want to move consumption towards daytime when peak supply is higher than demand.
I have solar, a powerwall battery, a high efficiency heat pump, and... a poorly insulated 70-year old home in Silicon Valley.
It can be wildly expensive to properly mitigate poor insulation: you need good air sealing, insulation around the entire building envelope, double or triple paned windows, and a different HVAC setup with dedicated fresh air ventilation. In other words, it requires a major remodel in some cases. Homes need to be built with energy efficiency as a top concern, and I wonder sometimes if that is going to require re-training and incentivizing the entire construction industry. Fewer than 1 in 10 contractors I talked to even knew what I was talking about when I asked for how they would do my project. "What's an ERV?" is a common question I heard. Many still think that gaps are good because "a house needs to breathe."
I have a 60 year old home and have made a huge dent in my winter therms and summer AC usage by simply adding some roof insulation and double-layer windows/sliding doors a few years ago.
Perfect is the enemy of good enough. You are not going to eliminate all gaps.
It currently shows that renewables are generating 145% of the total load. So what happens to the excess that isn't being used? Does it charge batteries to be used when the sun isn't shining and the wind isn't blowing? Is it exported to other states in real time? What happens to the excess energy that's generated by renewables during the day?
That's really confusing: If there is so much solar generated that they have to pay industrial user to consume electricity, why don't the solar companies just stop sending power to the grid instead of paying money? Are the solar companies unable to turn off their system due to a limitation in their system?
i suspect this could be related to the renewable production tax credit.
I think maybe it works out that the US government is paying, not the solar companies.
Why is there still a gigawatt of natural gas based energy being produced when energy costs are negative? Is pricing regional so some power is still valuable or something?
I'd guess it maybe takes time and money to ramp up/down natural gas capacity, so it makes financial sense to maintain capacity at a loss for now to better/more rapidly profit when solar capacity drops and prices go positive again? If I'm reading the day ahead chart on that page correctly, prices should go positive again around 5PM.
I'm definitely under the impression that that's the case for nuclear (which is famously bad at reacting to changing demand), but I would have thought that even slow gas plants could turn off for hours profitably. Could be wrong.
It could be that solar or wind can “shut down” much faster than offline natural gas can be brought online, so it’s better to run them at some sort of “idling” power than to turn them off entirely.
Plants will typically have a normal operating range (where the minimum is >0). A gas plant can respond fairly quickly within that range, but a cold start requires more time.
So they're paying money (or at least, producing little income) to keep the plants working when it is not needed, so that things are ready to go when it inevitably becomes possible for the plants to spool up and make money when their need increases.
Exactly. They can do this (i.e. keep producing power when the spot price is negative) because a plant that can respond rapidly to increased demand can charge a large premium in times of need.
Keep in mind it's not just generation that needs to shut down but also re-routing that power. Transmission lines and substations have certain capacities. Shutting down a gas plant for a few hours can mean transferring power from elsewhere in the grid over lines not really designed for that load. It could be easier/cheaper to keep the plant running than to build out higher capacity transmission to power that part of the grid.
Note you can toggle off sources in the chart by tapping on them in the legend.
Gas plants can respond quickly to changes in load, but they need to be up and running to do that. In the future this will be done with batteries but we don’t have enough of those yet. California does have about 20x more batteries than it did a few years ago, check out the Record Tracker link. There was a new record for battery discharging 5 days ago.
I thought that too on the graph, but I think that's a bug in labeling. When I look at the actual scale, that colour appears to be nuclear (and the other straight line is geothermal). This also makes more sense as they are sources that actually cannot be turned down to respond to electricity demand the way in which natural gas can.
I see 1.14 GW nuclear, and 1.1 GW natural gas at 12:20 PM PST, the nuclear is a flat line at the bottom of the graph (and I agree it makes sense), the natural gas is a dark blue section in the middle-ish, which shrunk from ~3GW overnight and does vary with time.
I don't think that what I'm seeing suggests a bug with labeling.
That'd be great if it could absorb the surplus, but right now at 12GW production it is curtailed at 0.29 GW. This means neither pumped storage, nor batteries, nor exports can deal with it.
On one hand it might create a new market, hopefully H2 electrolysis that replaces coal or gas in industrial processes rather than Bitcoin farms. On the other it also signals that any additional Solar is going to evict about as much capacity into such curtailments.
Anyway, California is the record-breaking market and all eyes are on it to helps us guide the global energy future.
I think this will be solved by decarbonisation of heat intensive industries. There’s some very good thermal storage battery solutions now, that can store thermal energy at hundreds of degrees C for a very long time.
So once there’s enough of this excess energy you’ll start to see industry soaking up as much of it as they can get.
If you “only” need ~200°C there’s some very powerful heat pumps entering the market that can give you more than 100% efficiency.
Long story, but basically there is a push in California gov't to deemphasize rooftop solar, in favor of big solar farms. (I've heard this is a favor to construction unions).
So we get paid very little per watt now, and it no longer balances out if you say use 20kWH from the grid and feed 20kWH to the grid (like it used to).
Joke's on them. Storage is getting very cheap now. At the prices PG&E is charging, it's now cost effective to buy batteries and store your solar power. Some of this requires a certain amount of DIY, but if PG&E restructures rates to go after these people, many of them will simply oversize their system, disconnect from the grid entirely and just have a generator for deep emergency backup.
> no longer balances out if you say use 20kWH from the grid and feed 20kWH to the grid
Should it balance though? One would presumably feed into the grid when sun is shining, meaning there's a lot of supply (not just from you), and consume during the opposite.
Yea, that's my understanding of the introduction of the NEM 3 policy. Production of energy isn't the problem in California (aka: sun), having it stored and accessible at the right moment is. Previously people would be feeding back solar during peak sun hours and getting paid, while taking energy at night and having an effective "0 dollar use" bill if they consume the exact same amount (there is some base connection fee).
The NEM 3 policy reduces a lot what you get paid unless you contribute back during the peak use hours, they say it's "avoided cost" pricing. On the surface it seems fair, you're paying for more than generation when you use energy so you generating and contributing back during huge surplus isn't as valuable as you using during night time.
Huh, thank you. Moved here recently so going to have to check it out. If I have battery storage to supply my home, surplus would at least make some money right?
Any resources in that? Seems ridiculous. I get a “net connection fee” and can even somewhat feel comfortable with this NEM 3 thing, but what I generate should be mine to control, I could do it completely off grid if I wanted.
As mentioned in other comment, moved here recently and exploring the situation.
Yeah it's really ridiculous and leaves me very cynical that California gov't cares anything about climate change aside from scaring people into more bureaucracy and power for themselves.
Another way to spin it: renewable electricity (except hydro) is literally worthless. You get it when you don't need it, but you don't have any guarantee it'll be available when you do.
„The venerable “baseload” concept—that grid stability needs gigawatt-scale, steadily operating thermal (steam-raising) power plants—reflects the valid and vital economic practice of dispatching power at least operating cost, so resources with lowest operating costs are run most. This traditional role of giant thermal plants led many people to suppose that such plants are always needed. But now that renewables with no fuel cost are taking over the “baseload” role of being dispatched whenever available, those big thermal plants are relegated to fewer operating hours, making the term “baseload” an obsolete honorific. Thermal plants must now adapt to follow the net load left after cost-effective efficiency, demand response, and real-time “base-cost” renewable supply have been dispatched. Nuclear power’s limited flexibility, and its technical and economic challenges when cycled, have thus become a handicap, complicating least-cost and stable grid operation with a rising share of zero-carbon, least-cost variable renewables. That is why Pacific Gas and Electric Company (PG&E) found that early closure of its well running Diablo Canyon reactors would save customers money and, by making the grid more flexible, raise renewables’ share. Those reactors had become cheaper to close than to run: the power systems’ shift to renewables had turned them from an asset to a liability, so they’ll be replaced by competitively procured low-carbon resources, saving both money and carbon.“
Take a look below at how much battery storage discharging (purple) offsets natural gas (maroon) after the sun sets in California on the hourly electricity origin graph. Not much further left to go at current battery deployment trajectories.
Conveniently, Tesla’s Megapack manufacturing facility is in Northern California, speeding deployments in state.
Which would be great if demand didn't vary by time of day and season.
But, it's neat the way that flaw has been rebranded as "baseload". The extra energy you need when people wake up and go to work? That's someone else's problem.
I’m gonna be blunt, that’s a strange position.
I mean, even just math wise/FFT, you can break down a lot of stuff into a dc component plus your variable component.
But the other part is you can absolutely adjust the output of a nuclear reactor, we just don’t because the availability is there. Look up the largest power stations in the us/globally, and sort by capacity factor.
It means they're exporting zero CO2 solar power and offsetting fossil-fuel-based-generation in the other state. You'll see that the imports value is also negative (implying exports).
I'm stunned to see upwards of 2 gigawatts of solar being curtailed at mid-day. As I understand it, those solar generators are producing beyond what the transmission grid can carry or beyond what native load there is.
Can anyone comment on what is the greater impact: transmission bottlenecks or lack of sufficient demand? FYI, my back of the envelope calculation for daily curtailment is 11.4 gigawatt-hours. I'm assuming that would be bigger but for the presence of battery storage on the grid.
3. Yes, you can see that batteries are charging from solar on CAISO Today's Outlook.
4. There is an enormous amount of home solar which shows up as a drop in "Demand": http://www.caiso.com/TodaysOutlook/Pages/index.html#section-... . Set the date widget to April 8, and notice "demand" rise to 20GW at the 11:15 partial eclipse peak and drop almost 6GW over the next couple hours. Figure > 10 GW of peak output from home solar
5. Grid and home solar together (> 25GW) are roughly comparable to total load (~26GW on this cool spring day).
6. Neither the transmission nor the distribution networks can efficiently send supply to load; both have bottlenecks.
7. This waste is an opportunity for more batteries, grid-scale electrolysis, etc.
8. A GWh is worth roughly $50,000. In the context of California's (~$4T/year ÷ 365=)$10B of daily economic activity, wasting $500k is not that big a deal. Particular matter from the state's natural gas plants kills many people a day.
Got sucked into this (shakes fist). EIA.gov estimates 16.6 GW nameplate of behind-the-meter solar at end of 2023 (having grown ~150MW/m through the year; it was 14.5 in January), generating 1.7 TWh/month in December and 3TWh in high summer, or 50GWh/day in winter and 100GWH/day in summer. If the growth continues at that rate, in July we will have 17.6GW generating 3.4TWh. Note that California has mandated panels on new buildings ...
What will the plan be to meet demand before sunrise? They've gone so heavy on solar there's not much scope to add wind to cover pre-sunrise. I assume they just keep installing more lithium ion batteries to the point they can run them all night, but I read somewhere that the cost sweet spot for lithium ion is 2-3 hours, although I don't know how reliable that claim was
The most recent(?) state plan: https://ww2.arb.ca.gov/sites/default/files/2022-11/2022-sp.p... . On page 203 you see the plan is 20GW of offshore wind, an enormous amount of storage and new solar, and smaller contributions from everything else. I'd bet enhanced geothermal and heat and iron storage would be weighted higher today. If we can permit it, we'll do it.
A lot is hanging on that 20 GW offshore wind. Would be a bummer to see permits canceled due to politics... I have a feeling the next administration may not have any good will toward California.
The mix graph does a pretty good job explaining why nuclear makes sense at night.
(Newer reactors use a big pool of molten salt as a battery and can time shift production. I wonder if the same trick could be used instead of grid-scale battery storage. I also wonder if it’s possible to play games with heat pumps to convert from electricity back to stored heat. That might be easier to ramp than new nuclear.)
Yeah, there's a bunch of British wind power which you can only see in public data as a small but noticeable dip in demand when there's wind power available. If you own a hilltop farm in England, unless your neighbours are complete assholes with political power (e.g billionaires or maybe MPs) you're going to install a small wind turbine because it's free electricity - it's not environmentalism it's just capitalism, and when it's blowing your small industrial processes are run off the turbine whereas when weather is calm you pay like anyone else. Needing a loan for a net-profitable business investment isn't a novelty for a farmer, and this one at least isn't predicated on future food prices - it's predicated on electricity costing money, so your bank manager will be happier.
Also, as a bonus, if you click this link[2] while logged in it will enable a preview of our nodal price map app which people tend to enjoy playing around with.
[0] https://blog.gridstatus.io/balancing-act/ [1] https://www.gridstatus.io/records/caiso [2] https://www.gridstatus.io/map?nodalMapPreview