The implementation possibilities for the AquaSolar technology in SGAs range from solar expansion and partial solar heating, right through to process heat. The areas of application are correspondingly varied, e.g. apartment buildings, hotels, restaurants, spa facilities, hospitals, barracks, gyms, open-air swimming pools, or office buildings; and for process heat, e.g. washing units, barn heating, breweries, the foodstuffs and beverages industry, the paper industry, the leather industry, catering kitchens or cleaning companies - basically any facilities which require large volumes of hot water with temperatures up to a maximum of 130°C.
Current SGA projects
By the middle of May, the market leader in evacuated tube collectors had received 343 queries, for a total gross collector surface area of 115,660 m², including 65 international projects with a gross collector surface area of 43,936 m². These include the subway washing facility in Coney Island, New York, shopping malls in the USA, the Springhill and Mt. Eden prisons in New Zealand, a reference system for the G8 summit in Hokkaido, Japan, and the Residential Tower in the Masdar project in Abu Dhabi. Other current projects include, for example, a district heating supply with a gross collector surface area which far exceeds 10,000 m², and another with a gross collector surface area of over 4,000 m². Already in November 2007, Paradigma installed the world's largest CPC evacuated tube collector system at Festo AG in Esslingen-Berkheim, Germany, with a gross collector surface area of 1,330 m². In summer, this system supports the cooling of over 27,000 m² of office space, and it contributes to the heating in winter. With a peak output of 1.2 MW and a maximum continuous output of 0.65 MW, it generates a guaranteed yield of 500 MW per annum.
The Aqua principle
In the "AquaSystem", Paradigma consistently uses only water as the heat transfer medium, and protects the collectors against frost with low-temperature heat from the system. Due to the CPC evacuated tube collectors' low heat losses, this requires only a small amount of energy, totalling between 2% and 4% of the annual solar energy yield, which is compensated for several times over by the advantages of water and high working temperatures. With the Aqua principle, which has proven itself in around 25,000 small-scale systems, Paradigma has overcome the obstacles for SGAs. Here, it was previously the case that the high temperatures for process heat could not be achieved with flat plate collectors. The solar yield generated with "summer collectors" was far too low, and therefore uneconomical. In addition, operators were put off by the ageing and replacement of the heat transfer media. With an AquaSystem, the solar energy system works like an additional boiler with freely selectable temperature. Solar heat exchangers, antifreeze, and additional fittings become superfluous, which reduces the costs significantly. Overheating problems are a thing of the past, which facilitates generation of up to 130° of process heat. As it is of no concern if the system stands idle in the absence of heat consumption, it is possible to use small, efficient storage tanks. Excellent thermal stratification in the storage tank, and a minimal storage tank requirement ensure extremely rapid availability of the solar heat. Over the year, around 50% of the electric pump running time and pump energy is saved in comparison to conventional operation. The controller's comprehensive functional monitoring detects and reports faults immediately, and thus guarantees optimal operation.
Market stimulation programme (MAP) problem
To date, the promotion of SGAs by the German Federal Ministry of the Environment has not been based on output but on gross collector surface area. For Dr. Rolf Meißner, this is an obvious disadvantage for solar tube technology. He explains: "The worse a solar collector performs, the more subsidisation it receives in relation to its output. This severely penalises CPC evacuated tube collector technology, which brings the highest annual yields by far, and which is the only feasible option for many process heat applications. Furthermore, the subsidisation legislation only promotes inefficient seasonal storage tanks, which would completely fail in the applications addressed here, while highly efficient short-term storage tanks are not explicitly promoted at all." Here, according to Meißner, there is an urgent need for improvement.
Internationalisation and expected sales
Due to the global market's increasing requirements, the Paradigma Group (of which Paradigma Energie- und Umwelttechnik GmbH & CO. KG is the parent company) is currently intensifying its cooperative ventures in France, Poland, England, Ireland and Canada. Klaus Taafel, Managing Director of Paradigma, lists additional steps toward internationalisation: "We are currently setting up a branch in the USA where, thanks to subsidisation, the market for solar collectors is growing rapidly. This year, we will also exhibit here for the first time at the industry trade fairs Solar 2008 in San Diego and Intersolar North America in San Francisco. In addition, we are currently establishing a branch in Bahrain for the exciting solar thermal market in the nations of the Gulf Region."
With Paradigma S.R.L. and Shandon Linuo Paradigma Co. Ltd., the Paradigma Group (which includes the 100% subsidiaries Ritter Solar GmbH & Co. KG and RNO Kesselfabrik GmbH & Co. KG) already has subsidiaries and joint ventures in Italy and China. In the first quarter of 2008 (January to April), the Paradigma Group was able to sell a total of around 231,641 m² of gross collector surface area. By the end of 2008, this should be over 1,164,500 m², compared to 641,206 m² of gross collector surface area in the 2007 financial year.
Further information: www.paradigma.de