apartment therapy changing the world, one room at a time

This is a great initiative. Mandating it levels the field for all developers, and buyers. Costs'll come down with much higher volumes of systems sold. Hurray!

WOW. Now that's really good news. We have the technology -- let's USE IT!!! OF course Hawaii gets a bit more sun than other places, but there are many, many eco-smart technologies that new homes can begin using NOW. Cool post.

On Kauai, the electric company offers a rebate for solar water heater installation every year. They also offer rebates for getting a new Energy Star fridge, etc. as rotating deals throughout the year. Other states must have programs like this...?

It's too bad that the law doesn't include new commercial buildings too!

There are also many neighborhoods in Hawaii that use catchment systems with cisterns for the rainwater, and aren't on a water grid of any kind.

the majority of homes where i live (israel) including apartment buildings are fitted with solar panels for heating water. some have electricity for back-up but with our long hot very sunny summers, the sun is our most efficient way of heating water.

super!
growing up my house had a solar hot water heater, not the fancy heat exchange kind but just the simple-run water in panels on roof- kind, which in Northern California works pretty well (you only have to drain it in the winter).
I will for sure put one on a house I own one day, it was basically free hot water half the year around, and less wear and tear on the hot water heater the rest of the time, its something like 30 years old and still going!

The only thing I wonder about is can you integrate them with on demand tankless heaters?

I live in a three story walk up in Toronto - not going to lie - the solar powered hot water was a definite selling point in deciding to move in : )

No all we have to do is extend this ruling to Florida, and make hybrids mandatory as cabs in NYC, and we'll REALLY be getting somewhere.

Oops... "NOW all we have to do"

I've always wondered why SoCal and the desert-y parts of Western US weren't 75% solar powered for heating and energy. Money and politics I suppose...but seeing something rational like this in Hawaii is great.

Those are now mandatory in Marburg, Germany too.

@CaliinFrance:
Tankless heaters are no problem, if you use those with a built-in power-adjustment. Usually you can choose a specific temperature. For example 38°C. (100.4°F) Or whatever temperature you whish.
Those heaters do adjust the required electric power.

Other heater, where you only can choose between "high" an "low" do not adjust the required electric power. Pre-heated water might evaporate inside the heater and cause some serious damage...

I think this is a great idea. My parents installed an in ground pool in the mid 80's and they couldn't imagine paying the hydro bill to keep it heated and we're a little homespun as is so they put up solar collectors, which is another form of solar heat which are large black panels on the back section of the roof and they have tubes which run the water through them when it's hot out thus keeping the pool a great temperature for summer.

I just found out (from that How Many Earths game) that Hawaii gets more electricity from petroleum than any other state!! Solar water heaters are a step in the right direction, anyway...