Solar cooling is currently still one of the less well-known technologies, as many customers are unaware that a solar plant can also be used for cooling purposes. The idea is in fact very simple. In summer, when there is an increased demand for cooling because of the solar radiation that occurs, the energy which is obtained is utilised to drive a thermal refrigerating machine that provides the necessary cooling capacity.
S.O.L.I.D. Gesellschaft für Solarinstallation und Design mbH awarded the “Solar Pioneer Award” of the Republic of Singapore for the plant “United World College - Solar Cooling” as the only solar thermal project. In cooperation with other Austrian technology experts like the company ÖkoTech, the plant is the largest solar cooling plant world-wide.
The technology for it comes from the city of Graz: the ultra-efficient “Gluatmugl” collectors, which occupy a space of 3,900 m², are manufactured by Oekotech, a subsidiary of the S.O.L.I.D Austria Group, and generate 2,200 MWh of green energy per year. This large-scale plant will deliver all of the hot water and an additional cooling load of up to 1.6 MW for standard air conditioning.
Solar energy is a solution that provides promising opportunities. It can be used in virtually all buildings to operate the cooling circuits and therefore to air-condition rooms. The cooling load is usually provided if solar energy is available and therefore the cooling demand of a building is approximately equivalent to the solar radiation. Solar air-conditioning systems are usually operated with entirely non-hazardous operating liquids such as water or brine solutions. A major project in Austria is also close to completion.
Barriers and Drivers
One important driving force for technologies like the solar cooling process is to correspond to EU's climate targets. These plants are operated with environmentally friendly refrigerants and they do not emit any CO2 emissions.
Also cost reduction and optimising the energy efficiency plays a major role.
An especially innovative trait of the project is the business model as the plant is realised in the framework of a contracting model. This was made possible with the support of the financing partners RLB bank Steiermark and the bank OEKB.
For solar cooling, only approx. 20 % of the power needed for conventional cooling is required. Ongoing energy costs are substantially reduced.
Compared to conventional cooling systems, the life time of the components of a solar plant is substantially longer (20-25 years).
Solar plants are environmentally friendly. Solar cooling reduces the burden on the environment to a minimum. These plants are operated with environmentally friendly refrigerants and they do not emit any CO2 emissions.
CO World Styria (www.eco.at)
picture source: S.O.L.I.D. © 2011