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Most net metering programs take solar from a home when the grid is facing its highest demand and energy is most expensive for the power company. They then provide a credit to your bill in watts. With a solar installation, you're drawing energy at night, when the grid basically wants to give away power to keep things balanced.

So you contribute a dollar worth of power, and you take out the same power at a later point in time, and the power company basically gives you a 5 cent credit.

The power companies make fistfulls of cash on the arbitrage.

They still hate it though, because distributed power generation threatens the model of power monopolies that get to fix prices while steadily reducing service.

Hawaii in particular has faced historically terrible load balancing, so some of the distributed generation is a response to the poor existing services and constant outages. HECO basically created all the incentives for the public to hate and want to work around them.

You couldn't just give them an out on whether they wanted to buy the power or not, since they despise distributed solar generation. They'd just build a messy and expensive quick spin up generator, buy expensive power from that during midday, and claim they don't "need" the solar, to deter investment in the technology, even though it'd be better for everyone if they bought the solar.

You can't ask a kid how much he needs foul tasting medicine. Sometimes you just have to deliver it.

You state the following as a given, which is exactly what your parent says is wrong.

>Most net metering programs take solar from a home when the grid is facing its highest demand and energy is most expensive for the power company. They then provide a credit to your bill in watts. With a solar installation, you're drawing energy at night, when the grid basically wants to give away power to keep things balanced.

Do you have a source that states production from solar meets peak demand?

We can take it as given that solar panels produce the most power during the day, particularly when the sun is directly overhead. The assumption is that air conditioning and refrigeration is a major electricity use that consumes the most power when the sun is shining. Presumably that is the case for residential, office, retail, and most service industry use. There are industries whose electricity use is not correlated with time of day, but they're not based in Hawai'i. If you want evidence that the damnedpowercompany would like to give away power at night, take a look at their awful "security light" programs.

I've seen a couple of things recently that said that peak consumption (in California, at least) is in late afternoon and early evening, as people return home from work and turn on their air conditioners and other appliances. It's not right in the middle of the day, as you might think.

Probably depends on where in California. If you look at google maps in SoCal, it seems like almost every house has a pool. Pool pumps take a lot of power, and you're supposed to run it during daytime. Those 4-6 hours its running is our highest power usage.

Pool heaters take a lot of power. Pumps not so much. You can defer heating until a couple hours before you want to use it.

I can literally look up my hourly power usage online. The 4-6 hours my pool pump is on is almost 2x higher power usage than any other time. I consider that a lot of power.

Edit: we had our house unoccupied for 2 months with everything unplugged and off, but our pool pump and sprinkler system. Based upon that, and looking at our historical usage, I would say our pool pump accounts for about 65% of our monthly kwh.

Wow, it surprises me that it's that high, but you clearly know your numbers. Presumably the rest of your house is quite energy efficient?

If it something that interests you, you could probably reduce the power usage considerably by switching to a smaller pump that runs for more hours. All else equal, the power required for pumps increases much more than linearly (proportional to the cube of the flow), so a pump with half the flow rate that is run for twice as long would use less than half the total energy per day for the same amount of water circulation.

Martin Holladay is a trustworthy source with a good writeup: http://www.greenbuildingadvisor.com/blogs/dept/musings/your-...

That's not the case for residential, office, an industry use. The hottest time of the day is when electricity tends to peak in hot climates, which is not when the sun is directly overhead. It's usually later in the afternoon.

In Hawaii, solar meets peak demand during the summer, as in the summer they have a higher midday peak than evening peak. In winter the evening peak is slightly higher, however if you look at area under the graph rather than just at the peaks, it is obvious that solar correlates pretty well with usage in general in Hawaii.

http://www.hawaiianelectric.com/portal/site/heco/menuitem.50...

Example data from Australia (peak at 6-8pm, clear power mismatch to solar): http://www.aph.gov.au/About_Parliament/Parliamentary_Departm...

That's not at all what that report says. The graph in the report is talking about the energy usage and production of one household, not global demand. Peak global demand of energy in Australia is very much in the middle of the day as offices and other workplaces run aircon / lighting / computers / industrial processes.

For the most part that's just not true, the peak is in the afternoon evening nearly everywhere. Here's lots of other examples: https://www.google.com/search?q=power+consumption+by+hour+of...

http://www.poplarnetwork.com/sites/default/files/peak-shavin... http://static.squarespace.com/static/545e40d0e4b054a6f8622bc... http://1.bp.blogspot.com/_nLHRC8dC8wI/S8tjxUq6cxI/AAAAAAAAAD... http://www.northcoastjournal.com/110305/chart.jpg

In CA, at least, net metering is in $, not Watt/hours. So I can push 1kWh to the grid in the daytime, when rates are high (typically $0.35/kWh), and pull at night when rates are low (typically $0.10/kWh). Thus, I can reduce my net bill to $0 while still being a net consumer on the grid.

Have an uncle who works in power. The way he tells it the power companies are happy with supplemental power during peak loading because peaker plants are unholy expensive, but said companies are worried about what is going to happen when everyone is doing it.

It's like electric cars & the gas tax. Electric cars are great! But gasoline taxes paid at the pump are a major source of funds for road maintenance, and electric cars pay none of them. That's ok for now because so few people have them. And that's not to say we don't want electric cars. But we better figure out how to handle them before half of the population is driving them and the DOT is faced with a major budget shortfall.

>I agree with the electric companies on this point. If they dont need the electricity, why should they be forced to buy it?

A) Because they are operating a utility monopoly. We are forced to be their customers. They should be forced to be ours.

B) They could use it, but they would rather sell you the output from their oil fired power stations because the profit is higher for them. That is why they don't want your solar panels hooked up - not because your neighbors couldn't use the electricity they generate - because it challenges their monopoly position and eats into their profit margins.

If this were truly about electric companies not needing the electricity (as opposed to them viewing any challenge to their monopoly as a 'free market evil'), then they would be arguing for market pricing for your solar generated electricity. They are not. They want your solar panels to be completely disconnected. Ideally you shouldn't even have them at all.

>Yes, its nice to sell back electricity to the grid, but that feels like a very hackish way to use 'solar'.

Your argument for how energy policy should be set are informed by what you think "feels hackish"?

I think you hit the nail on the head. Their monopoly is in jeopardy and they aren't happy about it.

Hawaii tried geothermal, but for some odd reason it made a loud whistle sound when letting off exhaust. People didn't like that, so the idea stopped cold.

I'd have just had some shitty engineer spend ten seconds proposing an easy fix for that, but then again if the power company gave me millions NOT to do that, why would i?

I'm really surprised people on HN don't see the complexity of having distributed power generation that you have no visibility on. I don't really think this is as trivial a problem as people seem to think it is.

As for the situation of selling power back to the grid, I would argue the solar users are still the customers. The power companies don't want it because the changes need to be paid for by current customers but only benefit ex-customers. The solar users are using the grid as a giant battery and an insurance policy for cloudy days.

If the power companies are paying what they charge, then the laws of physics say they are losing money due to losses to heat, etc. So of course their margins are higher on their power.

>I'm really surprised people on HN don't see the complexity

I never said it was a trivial problem. I said that it was a problem that the utility companies have a vested interest in not solving.

I'm really surprised that people on HN are blind to this.

>The power companies don't want it because the changes need to be paid for by current customers but only benefit ex-customers

This is false. The power companies do not want it even if it is paid for by current customers because even if it is, it eats away at their profit margins. Every kwh generated by a home owner's solar panel is not a kwh they are being paid for, even if they just use it themselves and don't transmit it across the grid.

At least in Hawaii there are a lot of independent energy producers, so your statement is appears to be wrong that they only want to sell their own power. While the majority is their own, it looks like 35%ish is independently generated.

They don't want to buy back power at the same rate they sell it, and since they can't control the nodes - the power from solar panels on homes is less valuable than that from larger independent producers since it costs more to control a distributed system. I'm sure they would buy it back, but people will be very angry about what they're willing to pay.

People are also free to get batteries if they don't like what the market prices are for buying electricity.

> I never said it was a trivial problem. I said that it was a problem that the utility companies have a vested interest in not solving.

They probably would solve it, but they know that the cost of solving that subtracted from the rate they pay their energy producers is low enough that people will complain and it's not worth it. They probably come out ahead by not solving that problem, I'm not sure how you can mandate they solve a problem so people that want to go "off grid" don't have to buy their own batteries. That's really what they're trying to avoid - there is nothing preventing people from going completely off grid, they just don't want to buy their own batteries.

>At least in Hawaii there are a lot of independent energy producers, so your statement is completely false that they only want to sell their own power.

They're not doing that because they want to.

>They don't want to buy back power at the same rate they sell it

They don't want to buy power at all. Certainly not if they have existing capacity that they would rather use. Definitely not if it is a future threat to their bottom line.

>People are also free to get batteries

Batteries are a much more inefficient way of using power than selling it to your neighbor.

>They probably would solve it, but they know that the cost of solving that subtracted from the rate they pay their energy producers is low enough that people will complain and it's not worth it.

Let's not pretend they're not solving the problem for our benefit. This is about their profits.

>I'm not sure how you can mandate they solve a problem so people that want to go "off grid" don't have to buy their own batteries.

Because they are a monopoly and a utility. We mandate they solve problems because otherwise they will just milk their monopoly for all its worth and the only party that benefits from that is them.

> then they would be arguing for market pricing for your solar generated electricity. They are not.

Market pricing is exactly what a lot of utilities in the EU are now pushing for. Solar panel owners don't like it, because market prices now frequently dip below zero when solar and wind peak simultaneously.

The second issue is the cost of providing and maintaining power transmission. Traditionally, the utilities just tack on transmission costs on the electricity costs. When everyone buys all their electricity from the utility, this is a reasonable compromise. However, when you get rooftop solar, the cost of providing power transmission to you doesn't go down at all, yet your electricity purchases do go down.

A fairer way to price electricity transmission would probably be by your maximum draw from the grid, or by the size of the fuse that connects you to it.

A fairer way would be to treat electricity transmission as the natural monopoly that it is and to ensure that companies that do generation are not involved in transmission and vice versa.

Transmission would be better handled by local government. If they want to favor homeowners' solar panels, so be it. If they want to favor the local power plant, again, so be it.

If you let generators run the grid then they will do everything in their power to kill any forms of competing power and they will succeed thanks to their monopoly power.

There is no intrinsic reason why rooftop solar shouldn't be given subsidies (direct or indirect), also. It is greener than almost all alternatives, after all.

> A fairer way would be to treat electricity transmission as the natural monopoly that it is and to ensure that companies that do generation are not involved in transmission and vice versa.

That's exactly how it works in Finland and a lot of the rest of Northern Europe. I buy transmission and electricity from different companies.

If the entire point of installing solar is to offset the cost of your own electricity, it seems like a incredibly stupid investment.

You are basically paying tens of thousands of dollars to shave $100 off your electricity bill every month. You would do far better investing your money in normal things and just using the profits to pay your electric bill.

If you want solar to not be reliant on the grid, you need batteries. If you want solar to be a investment that gives you xx$ of benefit a month, you should look into doing something besides solar.

Having just gotten our PV panel installed on our roof this year, this is fresh in my mind. Of course everyone is doing it -- electricity in Hawaii is insanely expensive. Before we turned on the system, we paid $200/month for power! And this is in a house with no heat and no AC.

Do they have to buy the power? Yes, but not without limits. The system is built on "net metering". Every kWh we deliver to the grid can only go to offset one that we already have or will use. If your system is so large so as to make you a net producer of energy when averaged over a whole year, you will be giving that away to the utility for free.

The rules also limit installation of PV systems to a level that will not exceed the minimum daytime load on the local circuit, exactly because there is nowhere to store the power. So every kWh they get from us is one they would otherwise have to generate to supply to one of my neighbors.

It's clear that the utility companies aren't happy with this. But studies have shown that these "extra costs" the utilities talk about being saddled with are offset by savings to them as well.

Solar power typically produces power during times of high power demand, so the net effect of solar is actually to even out the daily load variance. This is good for the utility because they need to make sure they have capacity to handle peak load, even if it's only for a small fraction of the time. These "peak power" plants are expensive, because you almost never get to operate them. When PV reduces peak load, they don't need these plants and this is a net win for them.

Could you just setup thousands of solar panels in a field you own and demand money from the grid? Seems like a easy return on investment, depending on the cost of panels/equipment

This depends on your jurisdiction; in the UK you can put up to 4kW on an inhabited building and get a subsidy. Larger installations require pre-approval.

Of course in the UK a 4kW system will rarely produce 4kW!

The laws are usually based on "net metering", so they probably only apply to the amount of electricity you can pass through a residential meter.

You are conflating the electricity producers with the grid. The grid itself actually saves money by installing storage, when compared to upgrading links, and does so when it can.

As to, if they do not need the power, why should they buy it? Well, there are two reasons, one is that everyone else on the grid already gets to, so it would be anti-competitive to not allow it for the little guys, and the other is that someone will always want power, so it makes economic sense to buy the power and build storage to offset it and make money through arbitrage.