Using the analytic categories from last year about reducing my carbon footprint, here are things I’ve explored and directions for 2016.
Substitution. In December 2014 we bought a 2010 Prius to replace Krista’s 1994 Subaru Legacy. The change in mpg was from mid-20s to high-30s (most of her driving is in Moscow, it does better on longer runs on the highway using cruise control so it can do more of the thinking).
Our milage data shows her car drove about 7300 miles in each 2014 and 2015, the latter with a 50% improvement in fuel efficiency.
Replacement. On the other hand, my work has me driving around Moscow. I find that I need to get between places faster, or take things larger, than bicycling facilitates. That is, I can’t achieve the driving reduction behavior I want, so I’m thinking about replacing my ’89 Toyota wagon with a used Nissan Leaf and moving to a carbon free automobile. I drive almost exclusively in Moscow and occasionally to Pullman and rarely to Lewiston. It seems the Leaf will meet my needs.
|Krista’s car (red)||7927||6313||7370|
|My car (white)||5241||2336||4472||4107|
|My pickup (blue)||1059||2078||1576||966|
|Krista’s Prius (silver)||7318|
In 2014 I gave away our 15 year old riding lawnmower/snowblower. For two years now I’ve contemplated replacing the remaining gas lawn mower (self-propelled walk behind) with a reel mower and/or an electric (corded or cordless) mower. I think a purchase needs to happen in 2016, even if I keep the gas mower as backup. Key issue is storage, I need a way to put either of those devices away out of the weather.
More Substitution. Karina and I used a Kill-A-Watt to measure the energy used by our refrigerator (part of a campaign to get a new fridge). Over a 3-day period (73.75 hrs) it used 9.06 KWH for an annual rate of 1076 KWH/yr. Karina has found replacement refrigerators with Energy Star ratings and energy usage ratings as low as 466KWH/yr and multiple options below 650KWH/yr. Now, realizing that the rating is like an EPA milage number (your milage may vary), it’s still hard to imagine we can’t get a better performing fridge.
We pulled out the fridge, it was made in Aug 1998 (17+ years ago). Googling how long a fridge lasts we found 3 sources: 80% last between 9-15 years; 10-15 years; and average 13 years.
SO, owning a refrigerator for its lifetime has 2 energy costs: operational cost and construction cost. One is paid daily, one is paid every 10-15 years.
As an aside, I wondered if there were a fridge that would pay for itself in energy savings (compared to keeping our current fridge (if it would last another 15 years)). I looked up the Avista power rate and multiplied by the KWH savings/year of our current vs potential new fridge = $45/year.
Karina was reluctant to search for a refrigerator that was 18+ cubic feet, 450KWH/year and priced under $700, but she found one (I think). Her reluctance stems from a desire to buy the features in the more expensive fridges she has found– which maybe should be a new category for this analysis: Too much vs Enough.
However, the analysis raised another question. When talking about payback period, are we talking the best sale price we can find, or the suggested retail price? That is, what does price measure: cost of inputs or other intangibles in the merchandising process?
Generation. I regularly observe that the solar air heater is in operation in the Cookhouse. I have resolved to get its water heater running. I intend that project to be the pilot one, with the home water heating to follow. The Barn is partly ready for solar hot water and solar air heating conversions, but it will be the third project to tackle. The house uses gas for hot water, the Barn uses gas for both water and space heating, so I have several opportunities to reduce direct carbon use through generation.