Modern air-conditioning systems use highly efficient electrically driven compressors to produce refrigeration and then cooled air. While highly efficient, these systems run on electricity which is expensive, particularly at summer peak times when demand is greatest.

Solar-enhanced systems.

The use of thermally driven chillers is a lower cost alternative to electrically driven air-conditioning . These chillers can utilize solar thermal energy to drive them and can be supplemented with cheap natural gas. The most efficient of these systems uses double effect chillers but requires high temperatures (around 350F) as a driving temperature. Such temperatures are beyond the capability of normal solar collectors but are perfect for Chromasun MCT Panels.

Solar Cooling Diagram


Advantages of thermally driven air-conditioning

Lower Costs: Gas prices are low today and peaking electricity prices are high. Thermally driven chillers provide air-conditioning at lower enegy costs than can electrically driven compressors. This is because they use solar and gas to run them, not electricity. Electricity costs are therefore eliminated and demand charges are reduced.

Solar Compatible: Thermally driven chillers are also compatible with efficient MCT panels which allow significant offsets in gas consumption and better environmental performance

Baseload Capability: Thermally driven chillers can be fired with solar or gas. The combination of the two energy sources means that these chillers can satisfy firm air-conditioning load factors with no backup required.

Reliable: Thermally driven chillers have few moving parts and a far longer design life than electrically driven mechanical vapor compressors. In addition Chromasun MCT Panels are also reliable, providing a sustainable onsite energy source that is backed up by natural gas which is not prone to blackout or peak summer demand limitations.

Efficient: Solar driven double effect chillers provide more cooling than comparative photovoltaic systems can. For a given roof area, far more chilled water can be supplied to the building using a thermal approach. Waste heat can be harvested easily as well and used as 'free' pool or DHW pre-heating where appropriate.


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    Chromasun assists mechanical engineers and building designers in engineering for solar. Chromasun also collaborates with Mechanical and General Contractors to source and install complete solar enhanced air-conditioning systems.

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