Geothermal power: The clean energy source you rarely hear about
Although geothermal energy may be a strong potential green energy source that doesn’t receive as much attention as things like solar energy, improvements in geothermal technologies are beginning to make headway.
A drilling technique that has been given new life and is under development by the US Navy and Sandia National Labs, is one of those improvements. Such improvements could eventually lead to making geothermal energy a viable option to reduce the usage of fossil fuels.
To create a geothermal power plant, a well is drilled deep underground, tapping into steam and hot water, created by the heat that’s naturally inside the earth. The heated water is pumped into the power plant, turning turbines. Once the water cools, it’s returned to the well.
Geothermal energy doesn’t require the burning of fossil fuels, so it’s a much cleaner type of energy than burning oil or coal. Geothermal plants do release some carbon dioxide gases, but it’s only a fraction of what’s found when burning fossil fuels. As another benefit, geothermal plants are built at the locations where the geothermal energy is available, meaning that transportation costs are minimized versus transporting oil and coal to traditional fossil fuel burning plants.
What has held back the use of geothermal plants are the start-up costs to create these plants. It’s really expensive to drill the geothermal wells and to create pump systems, as the early expenses make it more difficult for companies to make a profit on geothermal energy versus fossil fuels, which are much easier to obtain, deploy and use, at least from a cost standpoint.
That’s where the technical improvement developed by the Navy and Sandia enters the picture.
The drills that today are commonly used to create wells for oil and natural gas still make use of bits that were originally developed 30 years ago for geothermal drilling. These bits, called polycrystalline diamond compact, or PDC bits, never really caught on in the geothermal drilling industry, because of the complexity required to drill geothermal wells. However, the PDC bits were adapted for use in oil and gas wells, where the drilling techniques are easier.
Over the decades, the PDC bits have undergone improvements developed by the oil and gas industries, and the Navy and Sandia now believe these improvements, combined with their own research, will allow these bits to be used in a more efficient manner for their original purpose, creating geothermal wells. During initial testing, the PDC bits outperformed the traditional geothermal drilling bits by almost 300 percent.
While work will continue to make the PDC bits more efficient, this could be the kind of breakthrough that makes geothermal drilling much more cost effective. Once that occurs, we may finally start to see some serious headway from this source of green energy several years down the road.
As governments continue to try to find ways to create cleaner energy sources, geothermal is a great solution, so anything that can help to reduce costs and speed the drilling process could be the tipping point that makes geothermal energy a realistic financial option in the industry. There are just too many benefits to making use of geothermal energy to ignore this energy option.