New York Times: One part of the destruction wrought when Hurricane Sandy struck New York City was to heating and cooling systems. Local geothermal energy companies have had many building managers contact them to replace the damaged systems. Geothermal systems use a series of pipes drilled into the earth, where the fluid flowing through the pipes is heated and cooled by the earth itself. Digging and installing the systems can be difficult and expensive, but the annual savings on energy expenditures can be from 30% to 60%. And because most systems are closed and don’t involve any combustion, they require minimal maintenance and have longer lifespans. In New York City, more than 100 geothermal systems are already in operation. Most are for smaller buildings, because systems for larger buildings require more wells and therefore larger plots of land. Matt Donolli, a managing partner at Edwards & Zuck, says that a 500-unit multifamily building would require 10-15 wells.