Independent Electric Power

[hayden]

Several people brought up solar and other forms of independent electric power systems in a previous note and I thought I'd start one to focus on that topic without the debate over political policies and who caused California's current problems.

My place in Vermont is a 200 year old house that got electricity for the first time ever two years ago. It's completely off the grid and powered by solar panels and a backup generator. There's a battery bank for storage and an inverter to provide standard 120VAC power. Works great and was great fun to design and install. Operates just like a regular house, except the kids get yelled at a bit more when they leave the lights on. In the next year or two I hope to install a small hydro system to supplement the solar, especially in the winter when the sun is low and the heat runs a lot consuming electricity.

Peter

 

[blaze]

Peter,

A friend and I were having a conversation about solar power recently. We live in the sunshine state and would love to harness some of that resource. The big question is cost effectiveness. Do you see it paying for itself in a reasonable time frame? What are the limitations on power consumption; i.e. wattage?

Mike

 

[hayden]

If you have the grid in your house already, it's really not cost effective. I figured at one point that it was still around 5x the cost over 20 years, which is a long payback time. If you have to pay to get power brought to your house, as was my case, it's extreemly cost effective. For less than the cost of running in power, I get free power. Now that's a deal. But, as power rates go through the ceiling in some areas, it may start to make sense. Greater demand will also lower costs so it will become a self fulfilling prophesy.

By far the most cost effective thing to do is conserve power. Payback on switching to compact florescent bulbs, for example is typically less than 2 years. We've all grown so accustom to using power anytime and anyplace that it's not possible, let alone practical to convert a house to solar without first reducing your power consumption big time.

Any heating devices, for example, are completely out of the questions. Electric hot water, heat, stoves are completely out and need to be propane or natural gas. AC is completely out, but there are propane/natural gas AC units available. Next biggest consumer in your house is your fridge. There are high efficiency electric models available from companies like Sunfrost, and also propane fridges. Get rid off all this stuff and you'll find that lighting (with compact florescents) and the few other things needed consume very little power. We seldom run at more than 2-3 amps with the house in full operation. If you can get to this point you will have realized a huge chunk of the gains and never touched solar power.

We have propane heat (circulating hot water), hot water, and fridges. Lights are all compact florescent, and there is a TV, radios, washer/dryer (propane), dishwasher, etc. Coffee pot is electric but once brewed the coffee goes in a carraff and the heater get turned off, and my wife uses her hair dryer. It's thoughtfully set up and we live aware of our consumption, but not constrained in any way. And I have a tractor so I know the world is all OK.

In my experience people do solar or other renewable energy because they are building away from the grid and an independent power system is indeed more cost effective, or they have personal convictions that outweight the cost.

Conservation, on the other hand, I think is a no-brainer both from an economic standpoint and from a convictions standpoint. Cutting household consumption in half will make a huge difference in nation-wide electricty consumption.

 

[blaze]

You confirmed what I had thought. It sounds like the best use for solar in an area with existing power is on the assist side. i.e., solar hot water heat.

Your view on conserving what we currently have is right on target and I need to do a better job at that. I was made aware of just how much electricity is used when the lights are left on in the house. I just had new service, including a meter run to my barn. With just the radio on you can bearly see that meter move. I plugged in a 1000 watt light, then looked at the meter and it was spinning. I got to thinking, 1000 watts is only 10 lights left on in my house that are not really needed. I'll bet that happens all the time with my crew.

Thanks for the coaching.

Mike