Disclosed herein are methods, systems and devices providing efficient power plant waste energy and waste product recycling for use in other building structures, such as greenhouses. In some embodiments, heat from exhaust gas from a power plant is transferred to a liquid in a condenser, which can also remove impurities and contaminates from the exhaust gas and can increase the carbon dioxide concentration of the exhaust gas. The heated liquid is then used to provide heat to the greenhouse, while the exhaust gas is used to provide carbon dioxide to the greenhouse. In some embodiments, the condenser utilizing "return liquid" from the greenhouse. In some embodiments, the waste heat and waste products can be stored for later use.