Monday, November 1, 2010

Generating Off-Grid Power...

55 degrees outside - 12:03 pm - overcast and raining...

Living off-grid.  You know that it means no more utility bills and generating all of your own power, but what is involved in that?  No, it isn’t as easy as putting up a few solar panels on the roof and calling it good.  When it comes to generating off-grid power, there are a handful of methods that can be combined to generate all the energy you will need to live comfortably off-the-grid.  Listed below are three common off-grid power systems, two of which we will be making and using ourselves.

Solar Power  ---  Solar power is probably the one that jumps into mind for most of us when it comes to off-grid energy.  The sun-powered option, which includes photovoltaic solar panels, an inverter and batteries, can provide lots of electric power (especially if you get a lot of solar exposure where you live) for a long time, without any moving parts and a little maintenance.  The downside, at least for now, is the cost: it is rarely cost-effective to power an entire home entirely with solar power.  Add to that the wide variance of solar exposure by location and the fact that solar only works when the sun is shining.

We live in the Pacific Northwest, in the foot hills of the Cascade Mountain Range.  We rarely get enough solar exposure for a solar power system to power our entire home.  So in our case, we will not be using any solar panels at this time.  We will instead be using wind and water to power our home.

Wind Power  ---  Generating electricity from wind turbines is another option for off-grid energy.  Knowing the average and wind speed ranges, you can estimate how much electricity a given system will produce.  Keep in mind, wind speeds in a specific location can vary significantly from the area averages depending on local topography.

As with solar, there are pluses and minuses to going with wind energy off-grid; the biggest, most obvious one is the need for wind.  If the wind doesn’t blow, the wind turbine stays still and electricity isn’t being generated.  Wind turbines also have moving parts, which means more things that require maintenance and have the possibility of failure.  But if you have a good consistent stiff breeze blowing through the back yard (which we usually do), you can be consistently harvesting energy.

Water Power  ---  Probably the least-known of the off-grid energy systems is hydro electricity, which uses a source of running water, like a stream, to generate electricity.  It is produced from the energy in water flowing from a high level to a lower level that turns a turbine at the bottom end of the system.

Hydro electricity generation can be the most cost effective of the three.  It runs 24 hours a day, 7 days a week, providing lots of off-grid energy for a long, long time.  Because it produces so much more consistent energy, fewer batteries are needed to store the energy because there is less (or zero) time that the system isn’t generating energy.  Of course, as with the other two, it requires pretty specific on-site conditions; if you don’t have a stream in the backyard, you can’t use hydro power.

Our off-grid property is ideal for a water power system.  The west fork of a river bisects our lot and even though we are on top of a mountain, we have a lot of water in the ground.  We will be diverting most of the ground water into several drain ponds, in addition to being a nice landscape focal feature they will second as a hydro system that is located closer to our home.