Geothermal as a Green Energy Source
Geothermal energy is energy obtained by tapping heat from the earth itself. This comes from magma and the radioactive decay of uranium, thorium, and potassium. The downside to geothermal energy is the fact that it is expensive to build. On the other hand, because the earth's crust continuously decays replenishing the heat, it is still a renewable source of energy.
There are three types of geothermal plants around:
- Dry steam plants take steam out of fractures in the ground and use it to directly drive a turbine that spins a generator.
- Flash plants take on water at temperatures over 200 °C, out of the ground, and allows it to boil as it rises to the surface then separates the steam phase in steam/water separators which runs the steam through a turbine to generate electricity.
- Last, you have binary plants. Here, hot water flows through heat exchangers and that boiling organic fluid is what spins the turbine. Once power is generated, the condensed steam and remaining geothermal fluid from all three types of plants are injected back into the hot rock to pick up more heat.
If you were to compare the amount of energy collected from geothermal to solar, you still get more from the sun. However, unlike solar energy, geothermal technologies aren't hindered by a cloudy day. Geothermal energy is a green energy source because just like wind, hydropower and biofuel because it is renewable.
Solar Energy - New Discoveries
The day may not be far off when the use of solar energy becomes a norm.
There is now a deep conviction among experts that given a few years time, solar power will be in high demand that the cost will go down, inexpensive enough to undercut the prices of oil-generated electricity.
Previous predictions that it will still happen in a decade may no longer be true.
The anger generated by the recent prices in oil and its vulnerability to market forces and other events may have already been enough to polarized people, governments and scientific communities into seriously considering a reliable alternative energy source.
You can not get a source more reliable than the sun.
Even today homes that uses its power does not only benefit from the silent, energy generating, inexhaustible power of the sun, it also spikes up the prices of their homes.
Those that have solar powered homes are even reimbursed for the surplus power that they supply to the power grid.
Presently, heliostats, photovoltaic cells and plate collectors are being used to collect the energy by focusing these panels towards the sun or constructing and installing the panel's on spots where the sun shines most.
Development in technology as we all know often has a snowball effect. It never stops rediscovering and reinventing that the speed of development could often be surprisingly fast.