Seasonal storage of residential exhaust air and sewage waste heat

Most Finnish residential buildings have been built before ventilation heat recovery options became mandatory. Exhaust air pumps are an effective way to reduce emissions, but they cannot cover all heating demand. Ground-source can be designed meet loads, require corresponding amounts of space both above and below ground. This simulation study combines sewage waste with a ground-source pump system improve sustainability cost-effectiveness. A hybrid was shown 20% lower life cycle costs compared pure system. It also maintained sustainable ground temperature levels over the long term, while reducing above-ground requirements by 95%.