i hear more about wind than solar these days. 20 years ago i thought most homes would have some solar by now.
where i lived we lose power once or twice a year. Many people have natural gas backup generators. my understanding is rooftop solar feeds the grid and not a house directly. So, millions of homes have backup generators
Are we nearing any tipping point where local solar becomes a “big thing”?
> Are we nearing any tipping point where local solar becomes a “big thing”?
Probably not, tbh. Its getting a lot cheaper, but its really possible that subsidies will start getting smaller along the same time. In my area, rules to force utilities to allow net metering on good terms are trending weaker as well. The combination hurts solar competitiveness.
If the cost of powerwall type systems fell by at least 50% some of these things might change, as the utility interconnect might not be needed any more.
The utility interconnect really drives up the minimum price of solar because you have to go through licensed professionals who know you can't avoid them so there is no downward pressure on price unlike all other residential electrical (new construction notwithstanding).
Do your homework on that. In many areas you can hire a solar guy to do your last mile for $600 to $1000. Everything else is DIY and Alibaba. Just make sure to get county approval on the inverters and UL listed etc...
I've noticed that effect, but I don't think the problem is on the installer side. A big part of the cost for them is the "soft costs" and a part of that is dealing with sometimes intransigent personnel at power companies. There are horror stories of them needing to pester the company for months to get the final approval to energize the system, and that adds significant cost. The solar companies would love to get rid of this problem.
I don't think that I'd want someone that isn't a licensed roofer or electrician doing the installation work anyway.
Subsidies are in place to solve the chicken/egg problem of inducing demand and creating a new market. If solar panels are getting cheaper then subsidies should start to go away once targets are met. BTW, I still feel we're far away from withdrawing subsidies. Until we get below $1000/kw its still too steep for most homeowners. Currently, Florida is $2600/kw.
Oh, I agree and I have nothing against the subsidies getting scaled back over time. The issue is that it makes cost cutting in the industry less effective, as the savings don't always get directed to the buyer's bottom line.
I think it might create a long stall where solar doesn't really expand that much in consumer markets.
I have solar. So far, it feels like more of a "feel good" thing than a major economic benefit. Getting a 10kw solar array installed cost ~25k in our territory. Dealing with the local electric company was a huge pain, and the array doesn't actually feed the house (we sell power back to the grid). To really maximize the benefit, you need a powerwall, so you can store surplus energy, continue service during outages, and avoid taking a hit if the net metering agreement changes in the future. We're actually exploring this by way of the Ford F-150 lightning acting as a battery backup, but that also requires upgrading the house to a 400 amp service, so you really start feeling like you're getting in to sunk cost territory.
This was one of my major disappointments when I looked into solar the first time. I don't want to stick panels on top of my house that are basically just feeding back into the grid. I want to have panels that first feed my house, and maybe if there's extra feed it into the grid, but if the grid goes down I still have a more-or-less functional house. A big part of solar's value to me is the renewable, off-grid backup power. Solar has the interesting and useful characteristic that it keeps working even if things have really gone to pot and you've even lost gas and water for some reason. Having lots of houses like this scattered all over the place greatly increases civilizational resilience. (That is, I'm not so much trying to plan for "The End Of The World" just for me personally with my own solar install, but want the resilience at the societal level, and might be willing to pay to help it along.)
If solar's just going to feed back into the grid, I might as well just let the utility companies manage it themselves. It's more efficient than anything I can do myself.
Unfortunately, it seems like the way solar works helps that goal much less than I'd like. I hardly need multiple kilowatts of power backing a single functional outlet that almost seems begrudgingly provided.
I'd be interested in anyone who has experience in perhaps managing to set their house up the way I describe, what magic words to Google or say to installers to talk about this, and how much more money it may have been.
The real money ends up being in the power storage. Obviously there's such a thing as 'night' and multiple days without full sun (or snow on your roof depending on the area).
I wonder how many electric F-150s will get sold to people on the basis of using them as a whole-house battery.
I fully agree on your point of the lack of logic to grid-based solar. No doubt large scale facilities can be placed in better areas, be cheaper per watt, have higher uptime, are able to afford the more exotic power storage (dams for one).
Now, if it were me, I'd start with new construction designed around low power usage. LED lighting, efficient computers, chest freezer turned into a refrigerator, no electric heat or dryers or transfer fans for gas heaters. The sticking point would tend to be A/C but I think that can be mitigated via small house size, insulation, and use of efficient split systems. The smaller the electricity use the more tractable the problem.
I used to manage solar installations, couple of things:
1. Electrically, solar does feed your house first. It interconnects before the meter and into your main electric panel. The reason it doesn't work during an outage is because of regulations requiring solar to turn off during power outages so that electricians fixing downed lines don't have surprise power from random houses after they turn off the grid power.
2. If you want solar to work during an electric outage you need to install a battery backup that can feed it AC power and disconnect it from the grid during a grid failure. However, you need a pretty big battery to power a full house for a long time so it's generally cheaper and easier to have a gas generator backup if you are worried about this. Batteries are really just good for energy arbitrage purposes these days.
The term you are looking for is called islanding. When the grid goes down you want it to throw an automatic transfer switch and power your house from solar and/or batteries. When the grid returns, you want it to resync the AC wave and draw from the grid as needed. Check out the Victron Multiplus as an example.
My house is set up like you describe. The whole solar/battery system never interconnects with the grid, and is instead set up like a generator. There is a transfer switch to choose between "generator" power and grid power. If there is some exceptional weather and the battery gets too low, we switch to grid. If the battery is full and the day is sunny we often dump power into the car, air conditioning, or whatever.
That's one thing I've always wondered about solar. If it truly just flows back into the grid, and you don't get access to it during a power outage, surely a centralized solar energy installation would be a lot more efficient than installing them on everyone's roofs. You end up paying much higher installation and maintenance costs - the only real advantage is that it's a plot of land that's readily available.
It wouldn't surprise me (although I'm not any kind of power engineer) if a world of house-based grid-tied solar wouldn't be a bit of a management nightmare for the power company as opposed to large plants.
I expect we get away with it right now due to rarity.
South Australia has so much solar, at times there is zero grid demand. It is a management nightmare for grid operators, but that's what they're getting paid for (instead of generation, which is shifting to direct payment from consumers with solar on their roofs).
The future of grids is orchestration between variable demand and variable generation, along with pumped storage, battery storage, and long distance transmission.
I'm not sure about the 400 A comment either, but there's at least two "catches" to the F-150: it's ~$90k for that configuration and it's unclear how the charge/discharge duty cycle will affect it.
To be clear, even at $90k that's cheaper than buying a pile of power walls or similar. So it seems like it's a power wall array plus a free truck :).
Except if the truck is out of town on a fishing trip but the rest of the family is at home, the powerwall is unavailable to the family where the power is out.
The 90k price tag is for the highest trim model. The entry level is ~40k. We know the entry level won't be able to serve as a battery backup; however, there ostensibly a bunch of trim levels between entry and "ultra" with their own respective price points, and my understanding is that the details are still unclear regarding the lowest tier that supports this feature. If you have details, I'd love to see them.
Originally I read that the inverter is part of the truck and would not be included in the lowest "pro" trim model. After further research, it sounds like the bidirectional charging comes as part of the extended range battery upgrade, which you can apply to any trim model (starts at $10,000 and goes down in price at higher trim levels).
Generally electric vehicles handle wall -> charging.
Taking DC from batteries to connect to a 120V AC house is going to require an inverter which adds cost, weight, and space. Presumably the base model won't have it.
The charge station pro draws 80 amps. To use it safely, you need an outlet rated at 100 amps. My home is currently on a 200 amp service, and an electrician (also a close friend) told me I'd need a 400 amp service upgrade to provide adequate power to the whole house.
Large solar farms take up a lot of land. Much more than wind does. It also makes that land useless for anything else other than solar.
Large wind farms generate more power than solar on a per acre basis and have a lot of land that can be used for cow/sheep grazing, buildings for other purposes, and so on.
Solar is getting so cheap that people can use them for "local solar" (in the industry, that's called distributed generation).
Rooftop solar on residential homes usually power the house first, then the battery of the house, then the grid. This could change if net metering is allowed though but usually only after your batteries are topped up.
Also you could just not have batteries (since it's so expensive). In that case any excess power will just go directly to the grid.
Nothing and some companies are looking at that. It changes the dispatch characteristics but that's not a big deal.
I can see this happening more in the future when you kind of run out of space and have increased demand for power. First thing you'll probably do is upgrade the turbines to be bigger/more efficient. Then if you've maxed that out you can start adding solar panels underneath the turbines.
At the end of the day it's about lowering your costs to generate the power you need.
It's actually common for sheep to be grazed under solar and it helps keep the grass trimmer. Or the grassland can be managed for wildlife and polinators.
My guess is that solar sites will be managed to improve soil quality. And eventually we will rotate the fields under solar to give the soil a rest. It is the perfect opportunity for a win-win.
Yea, they graze under/around solar panels but that's pretty much all you can do for a solar farm. Wind gives you more opportunity to use the land.
I don't see the solar site management thing happening by the way. A lot of time and effort goes into land siting and selection. It won't be that easy to just pack it up and move.
Even where I live with a south facing roof and ample sunshine the pay off for a full system is something like 11 years - and after that I save $50/mo or some paltry amount. If it was reasonable I would get a small number of panels just to offsite the ToD pricing we have here (when the A/C needs to run the most) - but it seems that small installations are not cost effective in the end.
I think it would not be feasible to add these to most buildings. Wind power is very heavy and there are a lot of obvious wind forces acting on the structures. Buildings were not engineered to take those loads.
A city is literally the worst place for wind. High property values, low tolerance for visual blight and noise, expensive work forces for maintenance, difficult to access.. you want wind in places like farms, where land and labor are cheap, access is easy, and nobody is going to complain about the noise.
Also. They can create flickering sun which is unpleasant and unhealthy. During cold weather they can shed ice. And they might fall over or catch fire and hurt someone. A safety zone is an easy way to eliminate any danger to the public.
I'm rural and locals hate them, wish they were installed in the places where the demand is being created by the density of population: cities. There is considerable ostracization of any farmer who opts in.
Low tolerance for visual blight? We agree. We consider them a blight also, particularly for people who choose natural sights over the blight of concrete structures. Noise? Same thing. We hate the noise of any traffic and yet that noise is Ok here? The complaints are significant can't Labor is not a good argument. It's expensive here also. Specialty techs are needed and the drive time charges alone are exhorbitant.
These could be placed instead on the top of city buildings. It's been done already. You wouldn't hear the noise over the traffic or neighbors that live inches from you. No birds would be injured or migratory paths interrupted. Wildlife oaths would not be displaced. The visual is not an issue. You already have visual blight in a city.
The same thing that's preventing us from growing all our vegetables at the point of consumption with urban farming: it's a waste of valuable space! Put the people in the cities and the windmills out to sea, where they belong.
What is the endgame for not-on-demand renewables? I ask without prejudice.
We know we cannot yet store energy from wind and solar. So they are fine as contributors to the grid, but cannot really take the "power anytime" burden. Yet they are installed in huge numbers. What happens after a "critical mass" is installed?
Is it:
- Power companies are gaming the current environment, where marginal renewables are cheap, and take preference over fuel-driven plants (fossil or nuclear)?
- Is it a long bet on storage becoming cheap enough that renewables+storage (batteries?) are viable?
Depends on where in the world you are looking. For example, the EU has a price on CO2 which is going up to reach the EU goals with respect to CO2 emissions.
In that case, even if storage of electricity is expensive. At some it will be cheaper than burning fossil. Nobody really knows how new nuclear competes with storage.
If there is no price on CO2 (and now other regulations that limit fossil), then renewables just have to compete with fossil on price.
- overprovisioning because it's still cheap enough
- peak shaving with battery storage
- dynamic demand applications, powered by hours of "free" energy, taking them outside the peak demand: car charging, heat and cold buffers (aluminum smeltering, ice buffers for A/C), and lots more that will prop up
Your third item implies massive multi-trillion dollar upgrades to the transmission system(s) which are historically sexy and politically unpopular. They need to happen but they won't.
The end game is probably going to be a mixture of storage and moving energy intensive processes (e.g. aluminium smelting, hydrogen production, car charging) to when electricity is most abundant.
We can actually store energy from the grid. Not as inexpensive as generating it, but not unreasonable either. Most new solar/wind installs are now coming online with approximately 4 hours of battery backup.
Currently the shortfall is dispatched with conventional sources (mostly gas, coal and nuclear similar amounts). Battery prices continue to fall. Also new large storage facilities are coming online, such as compressed air which promise tens of Gigawatt-hours of storage at prices below battery. So that's the long term plan.
Actually if everyone had a personal power storage system they could probably reduce their bills alone with just that. Buy the power during the cheap hours and then use it later in the evening when it's 10 cents per kw more.
It is a long bet on renewables+storage. From easiest to hardest (and most efficient to least efficient):
- Renewables+batteries are already cheap enough for a few hours storage
- Flow batteries can go overnight to weeks
- Synthetic fuels (i.e. hydrogen, or synthetic hydrocarbons made with green hydrogen & CO2 captured from the air) can be stored indefinitely and transported globally
55 comments
[ 3.4 ms ] story [ 117 ms ] threadwhere i lived we lose power once or twice a year. Many people have natural gas backup generators. my understanding is rooftop solar feeds the grid and not a house directly. So, millions of homes have backup generators
Are we nearing any tipping point where local solar becomes a “big thing”?
Probably not, tbh. Its getting a lot cheaper, but its really possible that subsidies will start getting smaller along the same time. In my area, rules to force utilities to allow net metering on good terms are trending weaker as well. The combination hurts solar competitiveness.
If the cost of powerwall type systems fell by at least 50% some of these things might change, as the utility interconnect might not be needed any more.
I don't think that I'd want someone that isn't a licensed roofer or electrician doing the installation work anyway.
I think it might create a long stall where solar doesn't really expand that much in consumer markets.
If solar's just going to feed back into the grid, I might as well just let the utility companies manage it themselves. It's more efficient than anything I can do myself.
Unfortunately, it seems like the way solar works helps that goal much less than I'd like. I hardly need multiple kilowatts of power backing a single functional outlet that almost seems begrudgingly provided.
I'd be interested in anyone who has experience in perhaps managing to set their house up the way I describe, what magic words to Google or say to installers to talk about this, and how much more money it may have been.
I wonder how many electric F-150s will get sold to people on the basis of using them as a whole-house battery.
I fully agree on your point of the lack of logic to grid-based solar. No doubt large scale facilities can be placed in better areas, be cheaper per watt, have higher uptime, are able to afford the more exotic power storage (dams for one).
Now, if it were me, I'd start with new construction designed around low power usage. LED lighting, efficient computers, chest freezer turned into a refrigerator, no electric heat or dryers or transfer fans for gas heaters. The sticking point would tend to be A/C but I think that can be mitigated via small house size, insulation, and use of efficient split systems. The smaller the electricity use the more tractable the problem.
1. Electrically, solar does feed your house first. It interconnects before the meter and into your main electric panel. The reason it doesn't work during an outage is because of regulations requiring solar to turn off during power outages so that electricians fixing downed lines don't have surprise power from random houses after they turn off the grid power.
2. If you want solar to work during an electric outage you need to install a battery backup that can feed it AC power and disconnect it from the grid during a grid failure. However, you need a pretty big battery to power a full house for a long time so it's generally cheaper and easier to have a gas generator backup if you are worried about this. Batteries are really just good for energy arbitrage purposes these days.
3. There are inverters that have an outlet that works during grid outages, even without batteries (https://www.sma-sunny.com/us/how-to-explain-secure-power-sup...). They generally cost the same
I expect we get away with it right now due to rarity.
The future of grids is orchestration between variable demand and variable generation, along with pumped storage, battery storage, and long distance transmission.
I do like the F150 as a backup power source, but there's probably a catch. I see that a Tesla Powerwall holds 13.5 kWh, and the truck is 115-155 kWh.
Average US house is 30 kWh / day? It sounds doable but not cheap.
To be clear, even at $90k that's cheaper than buying a pile of power walls or similar. So it seems like it's a power wall array plus a free truck :).
Why is that? A missing feature?
https://www.f150gen14.com/forum/threads/trim-pricing-for-202...
Judging by this article [1], the bidirectional charging is maybe part of the $1000 "Pro Power" add on.
Either way, sounds like we can get a 100-ish kWh battery backup for $50k.
[1] https://autotrends.org/2021/03/01/what-is-bidirectional-char...
Taking DC from batteries to connect to a 120V AC house is going to require an inverter which adds cost, weight, and space. Presumably the base model won't have it.
Large wind farms generate more power than solar on a per acre basis and have a lot of land that can be used for cow/sheep grazing, buildings for other purposes, and so on.
Solar is getting so cheap that people can use them for "local solar" (in the industry, that's called distributed generation).
Rooftop solar on residential homes usually power the house first, then the battery of the house, then the grid. This could change if net metering is allowed though but usually only after your batteries are topped up.
Also you could just not have batteries (since it's so expensive). In that case any excess power will just go directly to the grid.
I can see this happening more in the future when you kind of run out of space and have increased demand for power. First thing you'll probably do is upgrade the turbines to be bigger/more efficient. Then if you've maxed that out you can start adding solar panels underneath the turbines.
At the end of the day it's about lowering your costs to generate the power you need.
My guess is that solar sites will be managed to improve soil quality. And eventually we will rotate the fields under solar to give the soil a rest. It is the perfect opportunity for a win-win.
I don't see the solar site management thing happening by the way. A lot of time and effort goes into land siting and selection. It won't be that easy to just pack it up and move.
you certainly don't want a city full of them.
Low tolerance for visual blight? We agree. We consider them a blight also, particularly for people who choose natural sights over the blight of concrete structures. Noise? Same thing. We hate the noise of any traffic and yet that noise is Ok here? The complaints are significant can't Labor is not a good argument. It's expensive here also. Specialty techs are needed and the drive time charges alone are exhorbitant.
These could be placed instead on the top of city buildings. It's been done already. You wouldn't hear the noise over the traffic or neighbors that live inches from you. No birds would be injured or migratory paths interrupted. Wildlife oaths would not be displaced. The visual is not an issue. You already have visual blight in a city.
And city dwellers created the huge need.
We know we cannot yet store energy from wind and solar. So they are fine as contributors to the grid, but cannot really take the "power anytime" burden. Yet they are installed in huge numbers. What happens after a "critical mass" is installed?
Is it:
- Power companies are gaming the current environment, where marginal renewables are cheap, and take preference over fuel-driven plants (fossil or nuclear)?
- Is it a long bet on storage becoming cheap enough that renewables+storage (batteries?) are viable?
- Something else?
In that case, even if storage of electricity is expensive. At some it will be cheaper than burning fossil. Nobody really knows how new nuclear competes with storage.
If there is no price on CO2 (and now other regulations that limit fossil), then renewables just have to compete with fossil on price.
- overprovisioning because it's still cheap enough
- peak shaving with battery storage
- dynamic demand applications, powered by hours of "free" energy, taking them outside the peak demand: car charging, heat and cold buffers (aluminum smeltering, ice buffers for A/C), and lots more that will prop up
- mix of sources. Solar+wind is more reliable than either solar or wind.
- geothermal
- interconnected grids. The wind is always blowing somewhere.
Aluminum smelters do everything in their power to avoid a situation where they lose power for more than a few hours and their pots freeze.
So you can dispatch for a few hours, but it adds enormous operational complexity if you can’t depend on 24x7 power.
Currently the shortfall is dispatched with conventional sources (mostly gas, coal and nuclear similar amounts). Battery prices continue to fall. Also new large storage facilities are coming online, such as compressed air which promise tens of Gigawatt-hours of storage at prices below battery. So that's the long term plan.
- Renewables+batteries are already cheap enough for a few hours storage
- Flow batteries can go overnight to weeks
- Synthetic fuels (i.e. hydrogen, or synthetic hydrocarbons made with green hydrogen & CO2 captured from the air) can be stored indefinitely and transported globally
https://www.energy.gov/eere/water/pumped-storage-hydropower
It is also popular in Europe.
More wind energy was installed in 2020 than any other energy source - https://news.ycombinator.com/item?id=28363813 - Aug 2021 (149 comments)