Monday, June 9, 2008

Heat Wave Tips: Cut Your Power Bill, Ease Grid Strain

The Green Miles is still wiped out from the big Climate Security Act throwdown last week, so just a quick post today. Lots of fun stuff in the pipeline though, promise.

With any heat wave inevitably comes talk of strain on our power grid and even brownouts, which power companies then use to shill for more power plants and transmission lines.

In the short term, so much of the burden could be eased if consumers took small steps to ease their usage. When you're leaving home in the morning, shut off your central air conditioning. It'll make a noticeable difference in your power bill:
The typical household keeps the thermostat set at 72 degrees in the summertime, adds Sheree McKenna, coordinator for Edison's in-home audit program. For every degree you hike that temperature, it saves you about 3% on the cooling portion of your energy bill, she says.

So if you raise the indoor temperature to 78 degrees in the summer, you save 18% on that portion of your bill. For a family spending $150 a month on air conditioning bills, that's a $27 monthly saving--enough to buy several new tank tops. They'll need them.

If you're out of the house for most of the day, consider pushing the thermostat even higher, [Southern California Edison engineer Tony] Pierce suggests. Although the house won't feel quite as refreshing when you step in, for every hour that your 4-ton air conditioning unit doesn't run, a family that's used more than its "baseline" energy allotment will save $3.36. Over a 20-workday month, that cuts your bill by $67.
Another common-sense tip - keep your house cool by keeping your curtains closed.

In the long term, smart-thinking utilities are coming up with wicked cool new ideas to reduce power consumption at peak times, like the Ambient Orb.

3 comments:

Brendan O'Connor said...

hola Miles, i hear that cutting the AC off totally just means it has to work harder when it's turned back on, and that it can make more sense to push it a little higher during the day and then bring it back down when you get in if need be--know anything on that?

TheGreenMiles said...

Brendan, I can't find that directly addressed anywhere, but it doesn't make sense. Leaving the air conditioning on during the day just means you're dropping dollars to keep your furniture cool while you're at work. All of the sites I can find say it's best to shut it down when it's not in use.

But if you have a large living space and it takes a while for the air conditioning to get it back down to a cool temperature, you can always get a programmable thermostat. You can set it to turn off the a/c just before you typically head to work and turn on just before you usually get home.

Brendan O'Connor said...

I'm not sure what to think. Like i said, i'd heard the opposite, and'll have to look into it more at some point too. But the idea does make some sense to me, though it may still not be correct, in the following way:

1st scenario-If i leave and it's 75 degrees in my apt., i cut it off, and the 90 degree weather outside bumps the indoor temp. up to 85 or 90 (or more) while i'm gone; then i come back, bump the AC on and it has to take it 10-15 degrees cooler at least

2nd scenario-If i leave and it's 75 in my apt., and i bump it up to 80 for hte period i'll be gone, and it's working all day to keep it cooler, but it only has to go 5 degrees cooler when i come back

So i guess the answer would lie in the detailed comparison of the energy it took to do the above. For scenario 1, it'd be the energy used at night to drop it back 10-15 degrees at least (and perhaps a little energy lost from the work it did the night before to cool the apt, that was then lost when it was turned off). In sc. 2, it'd be the energy used during the day to keep it cool, but less used at night than sc. 1 since it'd only have to drop 5 degrees lower when you come home. And in 2 you'd be at least benefit some from not losing the cool from the night before, since the AC isn't turned off.

Didn't think it'd take that much thinking, but still hard for me to say...we'll have to let one another know if we find something seemingly definitive on it...