An intended application for absorber roof is to provide the thermal input to a new type of engine.

These low grade, or low temperature heat engines come in a variety of forms and operating principals, but all hold similar promise. That is- a much more cost effective means of generating electricity, as well as the flexibility to run from other sources of heat.

There is a list of companies offering these systems on the Links page.

Uses for low grade solar thermal energy include

• Hot water
  

• Electricity generation using -

Organic rankine cycle
Closed loop hydrogen/helium cycles
Hydride engines
Matteran cycle
Kalina cycle

Thermo-electrics

Thermionics and quantum thermotunnelling

• Refrigeration using-

Ejector cooling

Absorbtion systems

thermally driven compression vapor cycles

• Space heating

• Water distillation

Many other industrial and agricultural uses

Absorber Roof could be suitably combined with small scale biomass conversion and/or generator waste heat. This would add value and flexibility to any co-generation arrangement, for times of year when solar insolation is low.

It may also be economical to use some form of thermal storage. This could be simply large insulated tanks of water, or phase change materials based on fats and oils, paraffin wax, etc.

For larger reservoirs and longer term storage, piping heat underground may be a good solution. Drilling techniques developed for geothermal heat pumps would make this quite simple. An example of how this is working can be found at Drake Landing Solar Community.