So in an effort to cut our annual electricity bill from 12000kWh to 10000kWh next year, I have successfully installed two LED outdoor security lights, an LED front-of-house candelabra style light fixture, and FOUR interior 40 watt LED bulbs (2 of on sale for $10 and 2 high performance $30(!) bulbs). Payback on all this will be about 15 months, at which time it’s all gravy. The old backyard security lights (100watt bulbs) ran about 15 hours per day at 50% dim. So:
100 watts (2 bulbs at 50%)
15 hours/day
365 days
547,500watt hours/year
547.5kWh/year
at .14 cents/kWh, the backyard lights cost us $76.65/year. Add in the front lights and we’re talking a little over $120/year to run. The new lights cost about $250 so that’s 2 years to pay them back. Still looking for a good LED replacement to go over the front door (preferably dimmable somehow).
We also got front and back storm doors, which will hopefully help in reducing drafts and air leakage. I also fixed a great big (1″ x 3″) hole in our front door frame a few months ago and it’s been a big help- mostly because now we don’t get overrun by rolly-poly bugs every few weeks.
I wish they made candelabra LED bulbs in a real-world 60 watts. I tried the “40 watt equivalent” type yesterday and they were dim and ghastly, so back they went. My office lights are a pair of 40 watt candelabra style that run about 15 hours per day. Total annual cost there is $60 in electricity (438kWh). If I replaced them with 10 watt LED’s I could cut that down to $15 (109kWh).
We’re just trying to grab some of the low-hanging energy fruit around here in an effort to lower the bills. We’ve even looked at a grid-tied solar panel system, but the roof isn’t the best for it (too many pipes jutting from our south-facing surface). The water heater needs to be replaced in the next year or so, so paying for a solar water heater might work, but our current heater is gas and the replacement will be so efficient that even if we added a solar heat backup system, the amortization time would be a couple of decades. If it was an electric heater we’d do it, but gas is still really cheap.
The thing I’d really like to do is replace our super cheap windows with good dual-pane argon filled ones, and then build supplementary interior thermal insulation panels to further increase insulation. But, wow, are new windows expensive. A full-house retrofit would cost about $15,000 and we’re not going to be here nearly long enough to justify that. Even so, standard walls have an insulation value (R-value) of 19. Our super cheap builder-grade windows have an R-value of…. one. Yes, one. So even adding a single layer of thermal insulation via a built-up interior window insert could save us 30% on our heating and cooling bills (according to online claims I’ve seen). That works out to hundreds of dollars per year for something that’s very cheap to build. The cheapest way is a wooden frame with plastic heat-shrink stretched across it. With my woodworking skills I think I could do much better than that- I’m thinking plexiglass laminate inserts with a second layer of plastic stretch material on the inside. This would create a double layer of insulating dead air space. I figure I could do it for about $50 per window. $600 for the whole house with a 2-3 year payback period.
The other obvious thing is to add insulation in the attic, which is probably in the cards sometime. I just wish we could super-insulate the walls, but that ship has sailed.
I would dearly love to take a few years and plan out a completely off-grid, super-insulated and self-sufficient house on paper and then build the thing myself. The thought of being free of all utilities– electric, water, gas, etc— is pretty appealing.
So that’s where we sit now in our energy conservation quest. 12000kWh last year, goal of 10,000kWh next year. A roughly 17% reduction in electrical use and an annual savings of almost $300. I’ll report back in a year and run the numbers to see what happens.
