Annualized Geo-Solar or AGS - Seasonal Solar Heat Storage

A different solar heating strategy based on capturing plentiful summer sunshine and storing it's heat directly in the earth beneath the energy-efficient homes. Solar Radiation is a very powerful source of energy, however it is intermittent. Some areas of the country have excellent winter radiation. Typically there is one quarter to one half of the energy available on an average winter day compared to an average summer day. The peaks and troughs can be leveled out, and heat carried over from day to day. The key is to have a large, well-insulated thermal mass under the house. Capital cost of such a system can be small - all that is required is a heat source like a greenhouse , sun space, a simple flat plate collector or the metal roof of the house itself, some 4" to 6" air tubes in the ground, a solar chimney or small PV fan, and some sub-grade perimeter insulation.

Geosolar Heat Storage

This is a simple system which, installed under a new home will allow storage heat from a Solar Collector. There should be insulation below the storage area and between the storage and slab, and the areas should be protected with a vapor barrier. The storage area should also be insulated at the sides.

Retrieving Heat

Normally there would be enough residual heat in the slab to carry through to late evening. For early mornings or bad weather it may be necessary to draw heat from the storage. This is controlled by a room thermostat which turns on the recirculating pump or fan , closes one zone valve and opens another zone valve . Heat will then be drawn from the storage to the slab. If the solar turns on, this circuit is over-ridden. This thermostat can be left on low for background heat. In an “off grid” situation this section has an isolation switch.