Climate control takes a lot of energy, and keeping your home warm in the winter and cool in the summer creates a lot of pollution if it doesn’t come from a renewable energy source. In the quest to make the world a greener place, geothermal energy looks like a promising candidate.
Harnessing the power of the earth itself, we can either cool or heat our homes. However, geothermal energy takes some preparation, and drilling a geothermal well is part of that process. Let’s take a look at these wells in greater detail.
What is a Geothermal Well?
A geothermal well is essentially a hole that is dug deep enough into the earth so that you can take advantage of the heat that comes from the planet’s core. While this may sound like you have to dig for miles to reach it, you’ll find that most geothermal wells are in the range of 150 to 400 feet deep.
As you would imagine, this is still a lot deeper than anyone can reasonably dig on their own, as you’ll need specialized equipment to do so. The good thing is that Geothermal wells aren’t that large, as the hole itself will only be about six inches in diameter, making the drilling operation a little simpler.
When people imagine geothermal wells, they often think of a hole reminiscent of Journey to the Center of the Earth, but the system is a lot more compact than that. Of course, the heat of the earth still isn’t enough to heat your entire home, so vertical loop systems such as these aren’t as simple as many people assume.
The heat transfer liquid that is pumped through your well will end up in a geothermal unit, which will slowly stockpile this heat and concentrate it. When it has collected enough heat from the ground, the geothermal unit will be able to circulate the heat through your home using vents or radiators.
Keep in mind that a geothermal well won’t only help heat your home, as it can also cool it off during the hotter months. Your geothermal unit will take the heat out of the air and transfer it underground using the transfer pipes. This makes a geothermal well a far more versatile and efficient method of climate control.
Geothermal Well Drilling Process
Drilling a geothermal well is a serious endeavor, and it’s usually the most complicated part of the entire installation process. There are specialized machines which are designed to drill geothermal wells called geothermal drill rigs, and they’re typically mounted on trucks so that they can get from place to place.
A drill rig will typically be around the same size as a cement mixer, and there is a massive gearbox that’s mounted on the back of the truck. This gearbox uses the energy of the motor to work the drill that will be creating the geothermal well, and it’s the most complicated piece of equipment on the drill rig.
The truck also contains several cutting shafts that are each around 30 feet long, and they are sequentially added as the drill reaches the maximum depth each time. Since each cutting shaft is added to the previous one, the drill can achieve the required depth for each job while remaining compact enough to be transported with relative ease.
When the drilling rig finishes its job, all it does is reverse the process, and the gearbox helps disconnect each of the shafts before storing them. Keep in mind that there are many different kinds of drill rigs that are designed for geothermal well drilling, and they come in all sorts of shapes and sizes.
Trucks designed for residential use will typically be a lot smaller than those which are used in industrial operations. Since something like a geothermal power plant will need to drill a lot deeper so that their wells are efficient, they often use specialized drilling rigs that are a lot bigger.
Geothermal Well Drilling Costs
The cost of drilling a geothermal well is highly dependent on where you are and how big the well is in the first place. If you’re looking to install a typical residential well, then you can expect to pay around 5000 dollars to have it drilled, and this doesn’t include the rest of the power system.
Of course, this can vary based on the depth of your well, but keep in mind that the price won’t change that much, for better or for worse. A geothermal well rig is a specialized piece of equipment, and due to the relatively low demand for their services, costs are still relatively high.
The only way to cut down on the cost of your geothermal well is if you have an industrial project and you need to dig several wells. For over ten wells, many businesses will cut off a sizeable portion of the cost, and prices nearing 3000 dollars per well are not unheard of.
Geothermal Well Depth per Ton
If you’re wondering how deep you should go based on the tonnage of piping you’ll be using, you have to keep in mind that these are only broad guidelines. Your ground conditions will have a huge impact on your geothermal system’s performance, so take these recommendations with a grain of salt.
Based on the contractor that you ask, you’ll get different estimates about the depth per ton which will be necessary. A common figure is about 200 feet of depth per ton of piping, but others recommend a more conservative estimate of 150 feet per ton.
In the end, we’d recommend taking a close look at your soil composition and discussing this matter in detail with the service that will be drilling your geothermal well.
We hope that we’ve been able to provide you with the necessary details about geothermal wells and how they’re drilled. While it may seem intimidating, geothermal energy is the way of the future, especially when you consider the growing number of households using it.