A reliable and renewable energy source is right under our feet – literally – in the form of geothermal energy. After funding a study a few years back to map underground hotspots, Google's parent company, Alphabet, has now spawned Dandelion, a new startup that aims to tap into that resource. The company's signature technology is a geothermal heating and cooling system that pumps heat from the ground into the home in winter, or out of it during summer.
The roots of the Dandelion system are what the company calls ground loops. These U-shaped plastic pipes are buried a few hundred feet under the yard, and water is pumped through them to provide the heating or cooling effects. In winter, water running through the loops will absorb heat from the ground and pipe it into the home, while the system will run in the opposite direction to keep things cool during the scorching summer months. The pipes are connected to a heat pump and water heater inside the house, and users can control the indoor climate through a smart thermostat.
Dandelion says that installation is relatively painless. To put in the ground loops, the company's own "clean drilling technology" will be used to dig a few small holes in the yard, each only a few inches wide. Then a technician will install the other components inside the house, and the system should be up and running in two to three days. After that, the only regular maintenance is an air filter change every six to 12 months.
The system reportedly costs US$20,000, but Dandelion is making it available to homeowners on a monthly payment plan with no upfront costs. If the system is as efficient as the company says it is, a user should be able to make some of those repayments through the savings it cuts off the household energy bill.
Dandelion was spun out of X, Alphabet's incubator for ambitious "moonshot" ideas. After securing $2 million in seed funding, Dandelion is currently rolling out the technology to viable homes in upstate New York.
Source: Dandelion
4000 ft of poly tubing is coiled and buried 8 feet deep in the front lawn area. The natural soil was used to back fill, but I suspect if you filled the trenching part way with bentonite slurry the system would have been more efficient.
I am a fan of geo-therm and so it is good to see efforts to make it affordable. If Alphabet has some magically advanced method or process which brings down the implementation cost, then perhaps it will help the industry...though this too seems unlikely given the $20K price tag.