Lots of reasons. Non-core business, long/uncertain payback (if power prices take a dive the payback extends), high upfront cost, a lot of regulation around feeding power into the grid.

[–] [email protected] 1 points 1 month ago (1 children)

Shouldn't those apply to residential too?

I guess it comes down to businesses needing to justify expenses and consider opportunity costs (not just the cost of solar panels vs nothing, but what the return would be if they took that money and invested in some other area vs cost of solar panels).

Residential customers are more likely to do it even if the payback isn't clear, because it sounds pretty good, they want to do it, and they have the money.

[–] [email protected] 2 points 1 month ago (2 children)

Yep, solar on residential doesn't make much sense unless you can load match your generation.

If you have people home during the day and run your aircon anyway. Maybe heat your hot water during the sunniest period. Maybe charge your electric car (if you have one at home).

If the regulations change to incentivize feed in to the grid, this can make it make sense, but it needs to be at least 80% of what you pay per unit; there are grid matching solar inverters that will do the matching for you.

[–] [email protected] 2 points 1 month ago (1 children)

Just to jump in here, residential solar makes a lot of sense for natural disaster resiliency. Your system would need to be sized to cover your bases in winter, but NZers should expect to experience days without power in a future where more Cyclone Gabrielle’s will occur. That’s why adding battery storage is a key part of it too.

[–] [email protected] 2 points 1 month ago

This is a good point, but for disaster resistance, you need to be able to run your fridge/freezer and charge your phone and radio.

A fire place for heating is a good bet. If you can afford it, a system sized to run your air con also would be great.

[–] [email protected] 1 points 1 month ago (1 children)

Battery storage for residential solar is getting popular, though this of course comes with additional cost that you then need to offset.

I'd like solar, and I don't really care if it has good payback so long as it's roughly break even. I'm part of the problem 😆

[–] [email protected] 2 points 1 month ago (1 children)

I understand.

If the feed in rate was ok, then it would be a good idea. But then again, if the power price keeps increasing, the solar + storage option starts looking good.

[–] [email protected] 1 points 1 month ago

Residential solar may also have another benefit over commercial. If the money wasn't spent on solar, it would probably be reallocated to the mortgage. But by allowing you to borrow money for solar at 1% and put the rest of the cash into the main mortgage at 7%, you get 6/7ths of the altetnate plan.

The 1% is only three years then it rolls onto a normal mortgage rate, but that's a big difference compared to companies whose borrowing cost is likely higher than the residential mortgage rate.

So residential solar is currently incentivised and commercial by comparison makes a lot less sense. So I guess this is where the govt could step in with subsidies or guarantees to reduce the cost to companies.