April 2016
« Mar   May »

My Case for Solar Energy

Today is Earth Day, so it seems like a good time to talk about alternative energy.

I’ve been fascinated with solar energy for a long time. Maybe it’s simple curiosity. Maybe it’s the engineer in me.

Or maybe it’s because the answer to one of our major problems is right there in front of us. You see I’m a strong believer that solar is THE answer to our long term energy needs.

I believe peak oil is real. I don’t know when it will really turn the corner to the point that we are forced to dramatically change our lifestyles. But I’m sure it’s going to happen. If not in my lifetime, certainly in my children’s.

A while ago, I heard a fact that caused the light bulb to go on in my head. Enough solar energy reaches the earth in 1 hour to supply all the earth’s energy needs for a year. We have a massive hydrogen fusion reactor perpetually supplying energy to us.

We simply need to learn how to harness it. The naysayers argue that it is inefficient. Sure it is. That’s why research is needed. If we had justified the space program strictly on economics, the United States never would have had a man walk on the moon. Instead, space exploration has led to many technological achievements that affect our everyday lives.

The government wastes money on a lot of things. Funding solar research would not be high on the list of money wasters. Cheap oil breeds laziness and discourages solar research. Sure we can wait until oil prices skyrocket and gas is $10/gallon. I think we should be doing solar research now before we’re trying to play catch-up.

A typical solar photovoltaic (PV) panel today is at best 15% efficient. Even at that, we were able to make it work financially on our property. I’ll go into much more detail in future posts about how we did that. If 15% efficient panels work, imagine what we could do with 30% or 40% efficiencies.

In the meantime, there other things you can do with solar besides generating electricity. If you don’t want to make the investment in solar panels, look into some of the other possibilities.

Water Heating

Water can be heated with solar energy very efficiently. We chose a solar pre-heater based on the concept of thermosiphon. The cold water supply lines to our natural gas water heater are diverted to the solar water heater where the water is heated before entering the traditional water heater. On a good day, the water enters the natural gas water heater at 130 degrees, requiring very little natural gas. There are many different designs so do your research.

Passive Solar Home Design

A lot can be accomplished to make a house easier to heat and cool without energy inputs. One example is using shades or awnings over southern facing windows. During the summer when the sun is high, the awning casts a shadow on the window which in turn lowers its temperature. Think of how you feel cooler in the shade in the summer. By keeping the window in shade, there is less solar heat gain into the house. Then in the winter when the sun is lower, the awning doesn’t cast a shadow on the window, allowing more solar heat gain into the house when you want it.

Another interesting design I’ve seen is a solar chimney. This works well in a sunny environment that isn’t too hot or humid. A vertical shaft is designed into the home with windows that intentionally cause the chimney to get very hot. A vent at the top allows the hot air to escape, drawing cooler air into the house with open windows in lower areas. You might think it is counterintuitive to intentionally heat up the vertical shaft, but that heat is quickly vented out the top due to the chimney effect.

Passive Solar Lighting

The sun’s rays can be used to light the interior of a house without electricity. This can be done with simple manual techniques like opening blinds or shutters to allow light in. Shutters can also be useful in keeping heat out in the summer and allowing it in during the winter.

A more sophisticated tool is a solar light tube. A clear dome is installed on the roof and a reflective duct routed down to a diffuser in the ceiling. The effect is very bright, natural sunlight illuminating the interior. Of course, they don’t work at night but fancier models include LED lighting for night use.

Solar Cooking

Solar energy can be used for cooking and dehydrating food. For more information, see my earlier post about the solar oven I built. An Inexpensive Easy-to-Build Solar Oven
Here’s an interesting article from Mother Earth News on how to build a solar dehydrator: http://www.motherearthnews.com/diy/tools/solar-food-dehydrator-plans-zm0z14jjzmar.aspx

What’s Next?

I was convinced years ago. We installed our solar water heater back in 2009, and started installing solar PV in 2010. I didn’t wait for it to get cheaper. I did it myself and it has paid off. In future posts, I’ll explain in a lot more detail how we did it. Follow my posts and maybe I can help you make an informed decision.

For now, you have to make your own decision. In can seem like a big investment. Do what works best for you.

One of Our Ground Mounted Solar Arrays

One of Our Ground Mounted Solar Arrays

Resources for this post:
An Inexpensive Easy-to-Build Solar Oven
Mother Earth News Article on Building a Solar Dehydrator
Solar Light Tubes

Please share your thoughts and opinions in the Comments.
To be notified of new posts, click on one of the links in the Subscribe section on the right.

Print Friendly, PDF & Email

Leave a Reply

You can use these HTML tags

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>