Monday, March 04, 2013

Passive Uses of Solar Energy

Actually, many of us make passive use of solar energy quite often...many times without even being aware of it.

For example, if you open the windows on the sunny side of your house on a winter day, you may actually be heating your home with energy from the sun, thus decreasing your heating costs.

A simpler example is making "sun tea" in a jug on the porch on even a relatively cool day.

Some people take this sort of thing one step further and actually design and build passive solar energy homes. These homes are oriented in such a manner that they can actually make the most effective use of the sun's rays for heating and lighting during the cooler months of the year.

Often, even the landscaping around these homes is planned so as to help maximize, or even minimize, the impact of sunlight on the home in order to achieve results. In this instance, plants may be selected which provide shade on the home in the heat of Summer, and then lose their leaves in Winter so that more sunlight can reach the home.

Sometimes, plants are selected and placed with the positioning of the sun at various times in mind. Again, in the Summer their shadows help keep the home cooler and in the winter, they are out of the pathway the sunlight takes to the home.

Most passive uses of solar energy are somewhat limited simply by the concept of passivity. If all you are doing is letting the sun shine on something in order to heat it up, you are usually only able to use this energy during daylight hours, and only in the form of direct heat or light.

However, much research has been done in the last few years on capturing and using this energy with specifically designed yet passive constructions. One of the more popular methods is to heat water with the sun and then store that heated water for future use. At the very least, available pre-heated water reduces the energy needed to heat the water the rest of the way for use in the home.

Often, to be effective, passive solar energy collection has to be combined with at least some small level of mechanical or electrical assistance. For example, an essentially passive water heating system may need a pump to move the heated water to a storage facility within the home, office, or outbuilding.

As with many aspects of alternative energy production and use, new passive uses of solar energy are constantly being developed, and old ones are being improved.

One drawback of passive uses of solar energy is that the homeowner is still needs connection to the conventional power grid in order to live in comfort year round. Many who get a taste of energy freedom by adding a passive energy system to an existing home, or build a new home with such systems integral to the design of the building decide they want to go "whole hog" and get "off the grid" completely.

In order to do this, they will have to add solar panels and/or wind power generators to the mix.

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