5 ms·

I can understand why it can be necessary, but why is being off-grid desirable? Having solar/wind/etc is great, but a grid connection gives you a bail-out in cas

I can understand why it can be necessary, but why is being off-grid desirable? Having solar/wind/etc is great, but a grid connection gives you a bail-out in case things go south, e.g. an outrageously hot and windless summer night might create a demand that cannot be handled by your battery (if any).

StillBored 5y ago
But your price in that case should be really outrageous because your just externalizing the cost of the utility having to build a peaker plant somewhere and run it on a couple peak days a year (and maintain the infra). That cost should be averaged over the year for someone who uses 100% grid electricity, but for someone who only uses it when the production is the most expensive then they are freeloading on everyone else. That is sorta the point of the whole article. It is also fundamentally the problem with wind and PV even at grid scale. Its true costs are buried behind the (generally) natural gas turbines being built to back it up because the grid can't just say "sorry no power right now, you get to freeze" like happened in TX last year. So, one has to take the max power usage, and assure there is capacity even if it happens to be dark/cold and without wind. Usually there is a fair bit of excess capacity in place to deal with plants have to shutdown for maint/etc so it just becomes a question of assuring that all the plants don't do maintenance at the same time (enron/CA anyone?), and they aren't going to be doing maintenance during the parts of the year when peak power draw happens (generally the dead of winter, and summer).
giantg2 5y ago
Well, if grid connected, then it wouldn't make sense to have a battery that is basically never used. Plus, you pay a fee just to be connected. If building a new house, I would rather save on the expensive hook-up cost. In the event of installing a system, I would want it to be sized appropriately and have proper design of the rest of the system. Better insulation, passive heating and cooling strategies, as well as a geothermal heat pump would all be good improvements. Arguably, those would the best to focus on before implementing solar due to the increased efficiency, reducing the necessary battery size, etc. Some of these my not be easy or practical with existing houses, but many are. Ideally I would like a solar/hydro setup, but that would require a property with a water source.
bick_nyers 5y ago
I don't agree with the parent commenter, but in some states/countries net metering is being turned around to having to pay a flat fee per kWh of solar generators. For example, my electric bill is around $160, I can net zero it out with 8kWh of solar costing me (installing it myself) about $8k total, but then if I get charged the $8 per kWh per month that is being proposed, I now pay $80/month to maintain a grid I rarely use as opposed to $0/month. Shifting my ROI from 4 -> 8 years. If you get solar installed with an installer, you would probably pay something like $20k for that same array, so your ROI goes from 10 -> 20 years, where your warranty might stop at 10 or 15 years. If you instead threw that $20k lump sum on the stock market and got 5% per year, you would match the amount you would have saved on solar. Edit: Math is hard, that's $64 a month and the numbers change slightly but the essence of what I'm saying still holds

StillBored 5y ago

But your price in that case should be really outrageous because your just externalizing the cost of the utility having to build a peaker plant somewhere and run it on a couple peak days a year (and maintain the infra). That cost should be averaged over the year for someone who uses 100% grid electricity, but for someone who only uses it when the production is the most expensive then they are freeloading on everyone else. That is sorta the point of the whole article. It is also fundamentally the problem with wind and PV even at grid scale. Its true costs are buried behind the (generally) natural gas turbines being built to back it up because the grid can't just say "sorry no power right now, you get to freeze" like happened in TX last year. So, one has to take the max power usage, and assure there is capacity even if it happens to be dark/cold and without wind. Usually there is a fair bit of excess capacity in place to deal with plants have to shutdown for maint/etc so it just becomes a question of assuring that all the plants don't do maintenance at the same time (enron/CA anyone?), and they aren't going to be doing maintenance during the parts of the year when peak power draw happens (generally the dead of winter, and summer).

giantg2 5y ago

Well, if grid connected, then it wouldn't make sense to have a battery that is basically never used. Plus, you pay a fee just to be connected. If building a new house, I would rather save on the expensive hook-up cost. In the event of installing a system, I would want it to be sized appropriately and have proper design of the rest of the system. Better insulation, passive heating and cooling strategies, as well as a geothermal heat pump would all be good improvements. Arguably, those would the best to focus on before implementing solar due to the increased efficiency, reducing the necessary battery size, etc. Some of these my not be easy or practical with existing houses, but many are. Ideally I would like a solar/hydro setup, but that would require a property with a water source.

bick_nyers 5y ago

I don't agree with the parent commenter, but in some states/countries net metering is being turned around to having to pay a flat fee per kWh of solar generators. For example, my electric bill is around $160, I can net zero it out with 8kWh of solar costing me (installing it myself) about $8k total, but then if I get charged the $8 per kWh per month that is being proposed, I now pay $80/month to maintain a grid I rarely use as opposed to $0/month. Shifting my ROI from 4 -> 8 years. If you get solar installed with an installer, you would probably pay something like $20k for that same array, so your ROI goes from 10 -> 20 years, where your warranty might stop at 10 or 15 years. If you instead threw that $20k lump sum on the stock market and got 5% per year, you would match the amount you would have saved on solar. Edit: Math is hard, that's $64 a month and the numbers change slightly but the essence of what I'm saying still holds