Renewable Energy Sources

There are benefits and downsides to all possible sources of energy. The important thing for us to understand is how each source works and what the benefits and downsides are so that we can properly way them against each other in order to make wise energy choices for our future. It seems to me that it will most likely be a balance of several types of energy that will help us in the long run to at least slow down our rapid loss of fossil fuels.

Solar power is one such alternative and renewable energy. “Solar energy originates with thermonuclear fusion in the Sun.” (Wright 377) Solar energy occurs when hydrogen nuclei (which is what the sun and stars are mostly made of) come together to create larger atoms (e.g. helium). (369) While some scientists have attempted to recreate this, it has not yet become effective for a variety of reasons. Therefore our greatest source of power created through the process of fusion is the sun itself.

The 2nd law of thermodynamics tells us that as energy is transferred, some is always lost. This loss is what would allow us to use solar energy without it changing the energy balance of the biosphere. (378) The solar constant is the amount of energy (1370 watts per square meter) that reaches the earth. (377) “About half of this energy actually makes it to Earth’s surface; 30% is reflected, and 20% is absorbed by the atmosphere.” Energy that is absorbed by water or land is eventually converted to heat and lost and even the part that is absorbed by plants is eventually lost as heat energy as the food is broken down by consumers. Also, any energy we would use would eventually become heat energy and be lost as well. (378)

Solar energy can and is being used in a variety of ways to decrease our dependency on fossil fuels. Water heating and space heating are two areas of energy use that would significantly lower the amount of fossil fuel we use if a larger majority would use solar energy for those purposes. There are of course some challenges with using solar energy. There is the question of, “What do we do when there is a significant amount of inclement weather.” In the Northwest we know that sunlight is limited for a long winter season and what about in the evening when the sun is down? Places like Alaska that have extremely long periods of darkness in the winter would greatly struggle to use solar energy.

“Solar power can also be used to produce electrical power, thus providing an alternative to coal, and nuclear power.” (382) Solar cells, called photovoltaic cells, are used to collect solar energy and put out electrical current. One cell can produce about 1 watt of power. (382) However, linking several cells together can create various amounts of power. Probably one of the most well known examples of this is the pocket calculator. The cost of these cells are high because of “their sophisticated design and construction.” (382) As the cost of them has been slowly coming down, they are being used more.

In order to make solar energy more widely used, the issues mentioned above and others would have to be answered in cost effective ways. It is difficult to get people to think past the here and now. So, if it is greatly less expensive to use fossil fuels for their energy needs, they will do so without much regard for the future. Just the other day I was speaking with someone about similar matters and that person said to me, “Well, if it’s good for my family and saves us money, I don’t really care about anything else.” Unfortunately I have a feeling that is a more prevalent attitude than we would like to admit. It is why companies like Wal-Mart are able to do the business they do. Perhaps we need to adopt a more “love your neighbor” type attitude that extends beyond our generation.

Wright, Richard T. Environmental Science Toward a Sustainable Future. New Jersey: Pearson Prentice-Hall, 2005.