[konschubert]

Your solar panels tend to produce power at times when power is cheap - because there is so much solar power.

When you do net metering, the utility has to pay on top: They have to sell the power that you produce on the spot market, but the price they get for it is less than what they have to pay to you.

It's not a scalable approach.

[Retric]

Solar also produces power when demand is at it’s absolute peak. It varies by location but prices are still cheapest at night the vast majority of the time.

There’s many ways to do net metering, but regulations are setup to maintain profitable local utilities. Utilities hate it because they make less money by selling less electricity not because it’s ever going to drive them to unprofitability.

[mcv]

I think the demand peak is in the evening. Whether that overlaps with daylight depends on the season. I suppose in areas where people use a lot of AC, peak demand might be earlier in the day, but I haven't seen any figures showing that. I have seen the evening peak.

[Retric]

It really depends on what you mean by peak demand. From the grid’s perspective a home with rooftop solar has zero demand during peak solar production.

However, that’s ignoring the home actually uses electricity during that period it’s demand simply isn’t something the utility can make money from.

Similarly, transmission losses increase as temperatures rise which requires more production to offset those losses. From the perspective of a natural gas power plant that load is just as real as actual customer demands because utilities need to pay for it.

Finally, time zone boundaries and suburbs being on the east or west of cities on the coast make a noticeable difference. https://www.dailymail.co.uk/sciencetech/article-2572317/Are-...

[kyriakos]

Maybe I'm wrong here but everyone seems to be considering only home use. During day time there's higher demand from factories and industrial processes even if home use its at its lowest.

[boulos]

Hmm? Why guess? Each provider has public sites with graphs of demand and generation. Here's the CalISO one: https://www.caiso.com/TodaysOutlook/Pages/default.aspx showing a funny camel shape today of an 8AM morning peak (heating) and then a 5:30 PM peak. What we can't see is the demand that would be placed on the grid around solar noon, if it weren't being serviced directly by panels.

Industrial and commercial customers often engage in Demand/Response programs though (primarily for building HVAC), so if there's a likely residential spike, they can shed some of their load.

[jjav]

> Your solar panels tend to produce power at times when power is cheap - because there is so much solar power.

But that's not true in how PG&E prices power. The very highest rates start when the day is just past warmest and sunniest (3pm) when there's tons of solar power available to feed into the grid. The cheapest rates start at midnight when solar contribution is obviously zero.