The concepts of solar, wind, and even water energy as a renewable power sources are not new by any stretch of the imagination. The sticking point for all of them has always been the same: the most reliable and economic way to store energy for later demand usage. The sun beats down during the day giving heat and light; there is less demand for electricity for lights and other items during the day when we are away from home at jobs and at school.
When we come home however, we like to have lights so that we do not bump into the furniture in the dark, and we like to be able to turn on the television for entertainment. Unfortunately, we do not have the sun to give us solar power at night; this means that we must be able to store that energy during the daytime to use when the sun has gone down. After all, no one has developed lunar power.
The best method for efficient, cost effective solar energy storage may be to store the heat in a solar thermal plant instead of storing the energy from the sun’s rays in a battery. A solar thermal plant creates energy by “boiling water into steam and spinning a turbine” (Wald 2008). By harnessing and storing this power, the owner of a solar thermal plant could then sell this power.
New methods of building the best and most profitable energy storage systems are being explored every day. One method that looks hopeful is the salt tank system. “Molten salt can reach extremely high temperatures without reaching high pressure” (Wald 2008). This means that the salt can be stored in a tank and heated as much or as often as needed without the fear of it building enough pressure to expand, breach, or burst the holding tank.
There are some drawbacks to the use of a thermal solar plant. The molten salt system can be housed in a tower, which is limited only by the size of the actual tower. Another system stores the salt in pipes which must be warmed constantly or the salt settles and becomes solid, clogging the pipes.
A photovoltaic plant can lose its power on cloudy or rainy days. This is a big concern in some areas, not as big in others. The amount of power that can be lost will vary but it can be enough to cause an energy provider some deep concern.