Replying to myself, to add some actual data for the drilling rig from another source: >Second, it has developed its own drilling rig–smaller and more nimble th

Replying to myself, to add some actual data for the drilling rig from another source: >Second, it has developed its own drilling rig–smaller and more nimble than traditional geothermal rigs. The custom-built machine is 19 feet long, 8 feet wide, and 8 feet tall, and weighs about 23,000 pounds compared to more than 70,000 pounds for a standard drilling rig. That means it can get closer to the house, and it won’t damage the grass so much, Hannun says. Third, it drills a smaller hole–4.5 inches wide instead of a standard 6 inches. That means less dirt and rock coming out and less grout with which to fill the gap between the pipe and the ground. A six-inch hole produces 662 gallons of “spoils” and uses 561 gallons of grout to fill, Hannun says. A 4.5-inch one produces only 372 gallons of spoils and 271 gallons of grout–a 50% materials and spoils reduction. At the same time, Dandelion’s rig collects all the waste, so it’s not spread across the yard, Hannun says. https://www.fastcompany.com/40440653/how-cheap-does-geothermal-need-to-be-before-it-becomes-the-next-solar https://www.fastcompany.com/40440653/how-cheap-does-geotherm... Unless the actual drilling technology has changed, it is nothing "new", an example of a "common" compact micropiling rig (also suitable for wells): http://www.massenzarigs.com/company/drilling-rig-mi4 http://www.massenzarigs.com/company/drilling-rig-mi4