Why Is Solar Energy More Efficient Than Conventional Energy?

Bernard says, "Solar energy relies on the energy created by the fires of the sun. Energy is measured in units of heat. Solar energy uses those units of heat produced by the sun to make electricity to run electrical and electronic products. Solar energy can also be used to heat water, which then becomes steam when it boils. That steam can be used to turn a turbine to generate electricity, or it can be used in collectors that are made out of silicon that somewhat passively turn that heat energy into electricity without the use of turbines."

The Encyclopædia Britannica says, "The potential for solar energy is enormous, since each day the Earth receives in the form of solar energy about 200,000 times the total world electrical-generating capacity. Unfortunately, though solar energy itself is free, the high cost of its collection, conversion, and storage has limited its exploitation."

When asked about the cost savings associated with solar energy, Bernard replied that when solar energy is used to make electricity, "I don't know that there's a cost savings per se, because the cost of solar panels can be quite expensive. But you would be saving yourself from having to purchase electricity. Depending on the size of your system, you will have to pay for the energy over a very long period of time. So it's kind of a wash economically."

There are also ways to harness the energy in the sun that don't involve converting it into electricity. When buildings are designed to use solar energy passively, they often generate cost savings in the long run. The Technology Fact Sheet from the government's Energy Efficiency and Renewable Energy Clearinghouse says, "It takes more thought to design with the sun; however, passive solar features such as additional glazing, added thermal mass, larger roof overhangs, or other shading features can pay for themselves. Since passive solar designs require substantially less mechanical heating and cooling capacity, savings can accrue from reduced unit size, installation, operation, and maintenance costs. Passive solar design techniques may therefore have a higher first cost but are often less expensive when the lower annual energy and maintenance costs are factored in over the life of the building."

Using solar energy has other important advantages. Bernard says, "You are saving the environment in terms of pollution and in terms of not using up non-renewable resources. You do not burn coal or gas to make electricity with solar energy. It's what we call 'sustainable.' Sustainable means if it's used, then it can be replaced. For example, when you make a tree out of wood, the tree grows back, so it sustains itself or replaces itself. If you use steel, on the other hand, a big hole gets dug in the ground, a huge amount of energy and resources are used to produce the steel, and the steel does not replace itself naturally. So things like steel and concrete, which don't replenish themselves, are not sustainable materials."