Technologies

Offices, plants and installations

Industrial Applications

Heating and Air Conditioning

The fuel cost and environmental consequences of heating or cooling a building with electricity or natural gas can be very significant. To offset these effects, several of Abengoa Solar's clients have opted to use the IST system for building heating and cooling.

In the summer, IST systems can utilize solar energy to run an absorption chiller. For more information on how an absorption chiller works please refer to the FAQ “How can I cool my building using heat from a solar field?”

In the winter, IST systems can capture solar energy for space heating. Below is a schematic of the solar heating and cooling system installed at Cochise College in Douglas, AZ.

To see different ways in which our systems have been used to provide space heating and cooling in the past, please see “Our Projects”.

In the diagram shown, the solar fluid circulates in a closed loop through the solar field and delivers heat to a pressurized hot water storage tank. Such a system using a heat exchanger in the tank would be used in a freezing climate where the collector fluid could be a water/anti-freeze solution or heat transfer oil. In a non-freezing climate, an open loop system can be used whereby the water in the tank is circulated through the solar field.

Whenever there is a demand for cooling and the tank is sufficiently hot, energy is pumped from the tank to power an absorption chiller to produce chilled water. This chilled water is delivered to the building load and reduces the amount of electricity consumed to power conventional air conditioning equipment. It is possible to produce and store chilled water to use for cooling after the sun goes down.

There is a good coincidence between the need for building cooling and the intensity of sunlight. Hence, solar air-conditioning can be an important means of reducing the need for utilities to build and operate power plants to meet peak electricity demands.

In the winter, when there is no demand for cooling, energy from the tank is delivered to the building space heating system.

District heating systems and industrial processes delivering hot water or energy for heating air, cooking or pasteurization require that solar energy be transferred to a liquid stream. This is accomplished by circulating a solar-heated fluid through a heat exchanger. Depending on the type of load, its temperature and pressure, a shell-and-tube or plate-frame heat exchanger can be used to interface with the load.

Links