Air-to-air, water source, and geothermal heat pumps might be the hot, new heating solution of tomorrow. Heat pumps are growing in popularity as a alternative to fossil fuel heating systems for buildings. Not only are they better for the environment, but they are also a cost-saving solution. According to the Tompkins County Energy Focus Area Study, “Heat pumps plus green building technology have proven to be a cost-effective construction technique, both in terms of first cost and operating expense and maintenance.” Heat pumps can be used for buildings both large and small, making it a heating solution that is just getting warmed up.