Can I afford not to waste electricity heating up my showers?
August 7, 2006 5:21 AM Subscribe
My old electric hot water service has sprung a leak, and I'm researching replacement options. Is there anything greener and
more cost-effective available to this Australian than off-peak electric?
posted by flabdablet to technology (11 answers total) 1 user marked this as a favorite
I've signed up for a 100% green electricity plan, so CO2 emissions are not a factor any more; but I don't much like the idea of using high-quality energy like electricity to generate below-boiling-temperature heat. It just seems wrong, especially in a country that gets so much sunshine.
The thing is, it's also cheap.
I've been using AU$270/year worth of electricity to run a 315 litre off-peak heater at 8c/kWh. An equivalent replacement will cost me $1100, so over its expected ten year service life I'd be up for $380/year to support our hot water habits.
I've looked at both heat pump and solar thermal options, and both of these tend to cost about $4000 up front; which even if they cost zero to run and/or maintain, means I'd still be behind at the end of their expected service lives.
In fact, heat pump units are generally not designed to run on off-peak electricity, because the air is cold at night and they don't work as well; so even if I used a heat pump and consumed only 1/3 of the energy, at 14c/kWh for untimed power I'd still be paying $160/year to run it. I can't justify this cost.
We get occasional nasty frosts here, which doesn't bode well for solar collectors - at least, not the type where the output water, as opposed to an isolated loop of glycol mix, runs though the panels. AFAIK the glycol types can't be retrofitted to an existing tank, either.
My town doesn't have reticulated natural gas, and I'd rather burn Queensland bagasse than Bass Strait gas or LPG in any case, so whatever I get is going to be at least somewhat electric.
Do I need to toss my energy-efficiency-advocate cred overboard to come out ahead, or can the hive mind show me options I've missed?