I just don't understand why Hawaii government has been so slow to mandate the most economically-net-positive renewables, given their astronomical electricity costs (old, shipped-in fuel, diesel-fired generators).
Solar hot water, solar PV, wind. Stop being held over a barrel with these electricity costs. They live in the most conducive place for it in the world, yet don't take advantage of it, really.
> I just don't understand why Hawaii government has been so slow
Island time is a real thing. And politics in Hawaii takes nepotism and "good old boys" networks to the next level. Things are the way they are because the people in charge are happy with it.
HART (the light rail system they're building) is a complete disaster, for the same reasons.
I can't see the government there being able to handle much of any major infrastructure project. The airport expansion is moving at a glacial pace as well. And it's a miracle the H3 ever got built.
The government has actually taken steps to push us down that road by mandating that all generation is renewable by 2045. Of course that's easy to say and harder to do, but I'm not sure it should be up to the government on how we get there.
The entity with the most responsibility to get there is HECO, which has a bit of a mixed record.
On one hand they have been pretty good about encouraging customer generation with net metering, and later grid supply options. Unfortunately there is a bit of an engineering problem there as we have pretty much reached the saturation of customer solar such that in the middle of cold sunny days, there is more electricity being produced than consumed (see duck/nessie curve). This would sound like a good thing, but with an extremely old grid and no utility level storage, it's kind of not.
A more reactive utility perhaps would have done a better job upgrading the grid to allow for distributed generation, but HECO spent the better part of the last 5 years trying to get themselves sold to a mainland utility to drive returns to shareholders instead of placing institutional focus on solving current or future problems for ratepayers. Serving two masters, etc.
Kauai has a much more interesting situation as their utility went through that whole sale to the mainland thing in the 90's, which failed and provided the opportunity for the ratepayers to buy the owners out and created a cooperative utility. I don't live there but from the outside looking in it looks like they are being much more proactive about renewables and more importantly, storage.
Absent some kind of massive game changer in wave or wind generation, the whole game is really storage. I know a lot of people who would love to install solar, but HECO is already at max capacity absent a way to store electricity at scale.
Finally the part that gets talked about the least is economic inequality. Hawaii's real estate is expensive, but it is driven by investment from outside the state, making it almost impossible for people who live here to afford homes. That interacts with the energy piece because you have to be a homeowner to benefit from solar, so solar contributes to wealth inequality as people who are fortunate enough to own homes also reap the benefits of government subsidies and cheap electricity, while people too poor to own homes are left paying the retail rates. And this is before we even get into the distortions of behavior that net metering encourages when you treat a kwh of solar in the day as equal to a kwh of petroleum at night.
Is it? Solar PV overall efficiency is probably 15-20% of the incoming solar power. While, a solar thermal hot water system can reach 50% or higher efficiency, even accounting for storing the hot water for several hours.
Solar thermal also just requires fairly cheap mirror like surfaces, while solar PV requires semiconductor chips.
Heat pumps are at the 400% efficiency level so by your numbers they're already ahead. And PV has other advantages. It's easier to install since it doesn't require specific tubing and the panels are much lighter. The energy is useful for other things when you don't need as much hot water. And efficiency goes up in winter because PV is more efficient in the cold whereas efficiency of thermal solar goes down as you need to heat the panel before heating the water. It will depend on your local PV and heat pump costs but thermal solar seems less and less relevant these days.
AIUI, ground source heat pumps get really expensive when the ground is really hard. A reasonable proxy is “do your neighbors have basements?” If the answer is “no”, then it’s probably because digging is more trouble than it’s worth.
Efficiency is still good for air source heat pumps IIRC. They only go down to 100% at well below freezing which is probably not a problem in Hawaii. Ground source only requires a small hole though, of the kind that is done for water. I'm in a granite rich area where basements are very rare but water wells are very common and reasonable cost to drill.
> “do your neighbors have basements?” If the answer is “no”, then it’s probably because digging is more trouble than it’s worth.
Basements are popular in cold climates because footings already need to be dug several feet down to get below the frost line. In warmer areas, basements are uncommon even if digging is easy.
Oh, well I mean for simple cheap residential don't-have-a-lot-of-money-to-spend, a do it yourself hot water solar system is just about the cheapest, easiest thing you can do, right?
Out of state folks are investing into 8,000 acres of solar plant in central Ohio. My guess is that there are material administrative impediments to the process rather than lack of demand.
Solar hot water, solar PV, wind. Stop being held over a barrel with these electricity costs. They live in the most conducive place for it in the world, yet don't take advantage of it, really.