When we moved from an apartment to a house recently, I saw it as an opportunity to explore energy efficiency. I knew that switching to more efficient alternatives usually doesn’t pay off for a period of time, so I figured we should start immediately and reap the benefits for as long as possible.
I was very surprised to learn just how quickly some things pay for themselves and how much of a no-brainer certain things are. The government as well as local utilities also have a bunch of rebates, making things an ever better deal. Here is some of what I’ve learned
Solar in Las Vegas is a complete no-brainer as the city has more hours of sunshine per year than any other major city in the US. The payback period varies, but it’s around 7 years. However, panels do add some value to your house for resale, so the payback period is shorter than that in reality.
You can finance solar at such low rates that your solar system payment will be about half of what your electricity bill would be. So if you know you’re going to live in the house for a long time, it’s definitely worth it.
One interesting hack is that the solar company will give you extremely low rates (we got .99%) but add points to the purchase to make it more expensive. Once you get your federal rebate you’re supposed to pay it back to the financing company to lower your payment, but it is dumb to pay off .99% loans, so you can actually just invest it in something safe and use the interest to pay off the solar loan, making it even cheaper.
When you create electricity in excess of your house’s needs, you are credited with 75% of the value of that electricity. The trick is that during peak summer hours electricity is worth 35 cents per kWh, but during other hours it’s worth only 3.5 cents. So every kWh you can generate during those hours will give you 7.5kwH of off-peak time. This is especially good for travelers, as a few weeks away from home in the summer could generate six months of bill credits.
I have also implemented some home-automation tasks like turning off my EV charger during peak hours.
We went with a 12.24kW system, which was a total guess. What I learned is that if you generate too many bill credits you can’t cash them in, but if you aren’t generated enough solar you can always add panels at the same price per watt, or possibly cheaper if/when prices fall.
If you have an electric vehicle you also get about 10% off all power from 10pm to 8am, including non EV power.
As I previously wrote, I bought a BMW i3. It’s the absolute perfect EV for city driving because it can go 60-70 miles on battery, but it also has a little generator to charge itself so you don’t have to worry about running out of range. It also happens to be one of the most efficient EVs ever made. It costs me .8 cents to travel one mile, versus about 10 cents per mile in a regular gas car (or 40 cents in the Bentley). The car will never pay for itself in savings, but it does save hundreds per year in costs. If you’re like a normal person who buys a car, drives it for a while, and then resells it, those hundreds saved may actually cover the depreciation.
It’s also more satisfying than I thought it would be to have a closed loop system where photons hit my roof, are converted to electricity, are stored in my car, and then allow me to drive around. I also like knowing that I’m always at full range and probably only have to go to a gas station once every year or two for a couple gallons.
I was shocked to discover that pool pumps pay off more quickly than anything else! Pool pumps serve two functions, the first is to skim debris off the surface of the pool and the second is to move the water around enough to avoid algae. Skimming takes 2-3 hours per day, but water needs to be moving for at least 12 hours per day to keep the water from growing algae.
Almost every pool pump is one speed, and because skimming requires a lot of water movement, that speed is high. A variable speed pump can run for 2-3 hours on high for the skimming and then revert to very low flow for 12 hours to prevent algae build up. Low flow uses only about 10% of the power of high. I bought a $500 variable pump on ebay, tried to install it myself, failed, hired a pro to do it, and even after paying him it will pay off in about 1-1.5 years.
Even better, it is silent on low, even if you’re right next to it. Before you could hear the loud pool pump in our backyard at all times. Now I have it run on high in the middle of the night for a couple hours, then putter around on low all day.
Hybrid Water Heater
My friend found a crazy deal on a hybrid water heater. Normally it went for $1700, but with coupons and rebates we could get it for only $400. Our water heater was nearing the end of its service life, so I jumped on the deal.
In researching this water heater, I learned something absolutely fascinating. How efficient do you think a heater can be? I would have bet everything on 99-100%, because I know that heating elements are 100% efficient. They convert 100% of electricity into heat. As it turns out, heat pumps are MORE than 100% efficient. How? They “carry” heat from the air (all air has heat because it’s above 0 degrees Kelvin), and are able to carry more BTUs of heat than they could create with the same amount of electricity.
This absolutely blew my mind. AC units that we have on our houses are heat pumps (they carry heat out of our house), and they run on reverse to heat the house, carrying heat in. This is why space heaters are SO expensive compared to central units.
A hybrid water heater is a typical tank heater except that it has a heat pump on the top. It is so much more efficient than a regular water heater that it will pay itself off in about 1-1.5 years for the deal I got, and around 5 years normally. It may only save a few hundred per year, but I am so enamored with the technology that at least once a week I think about our water heater and how much I love it.
LED Light Bulbs
This is a no brainer and I’m sure everyone here has LED light bulbs. Something interesting to note is that running an LED light bulb at really low dimness settings uses nearly no electricity but can create usable light. I have all of our lights in the house on all evening at 5-10%, mostly in warm orange colors, and it creates great atmosphere.
I feel good that the changes we made to our house our good for the environment, but I’ve focused mostly on the cost savings and other benefits because I think those are the factors by which we make most decisions. As someone who is a little bit obsessed with runway and low living costs, I also like that we can spend a little bit of money up front to permanently lower our costs.
Photo is the Hoover Dam from Lake Mead. How cool is hydroelectricity?
This Sunday at 12pm PST I wil be hosting Tea Time with Tynan #3! We will have a loose topic of home improvement / home automation / workspace / etc, but you can come on and ask about anything. Please join!