The ISH 2013 Design Plus Award goes to: Austrian Kioto Group’s Solcrafte Style. Out of the nearly 200 submissions from 15 countries, the jury recognised 34 as particularly outstanding, including Kioto’s integrated storage collector, the only solar thermal product among the winners. The international trade fair for innovative bathroom design, energy-efficient heating and air-conditioning technology and renewable energies, took place in Frankfurt, Germany, from 12 to 16 March 2013.
The international competition “Design Plus powered by ISH” honours sustainable products which combine innovative design with energy-efficient technology. “Solcrafte represents a new generation in designing compact solar solutions,” says Stefan Verhounig, Solcrafte’s Product Manager. “Solcrafte Style differs from conventional thermosiphon systems in that the heat storage tank has been integrated into the collector. We have improved the classic 2-circuit thermosiphon design to create a compact, non-pumped single-circuit system. By eliminating various components, such as solar pumps, heat exchangers and combined storage tanks, Solcrafte Style is more compact, saves space and requires less maintenance.”
The collectors are available in three sizes with a surface from 1.1 to 2.4 m² and tanks holding 90 to 195 litres. The casing is made of aluminium and is well insulated with a rigid 30 mm polyurethane foam sheet. The tank inside the collector consists of special stainless steel pipes with a highly absorbent coating. According to Kioto, the collector performance ranges high above comparable thermosiphon systems. The manufacturer has identified annual yields between 780 and 1,880 kWh for the three models in Rom, Italy. These values translate into a solar fraction of 74 to 88% for water heating. “We have introduced the collector in Southern Italy in 2010 and have sold more than 10,000 units in the meantime,” says Verhounig.
Integrated storage collectors are simple, compact and effective and therefore the best choice when a lack of space or money prevents the purchase of a conventional solar thermal system. In recent years, an increasing number of solar manufacturers has entered this segment, supplying the market with appropriately small systems. Other examples are the Nanosol NA 130 introduced by Turkish collector manufacturer Ezinç Metal in 2012 or the OKSOL-150, a pumped PV-driven system by Spanish company Orkli.
“Our Nanosol collectors have been well accepted by the market,” Fatih Icik from Ezinc’s Export Department said at the ISH fair. “This product allows us to actually focus on North Africa. But now, it seems to have also sparked great interest in Italy and even in the Baltic countries.”
Nanosol NA 130, a direct passive system, resembles a satellite dish with a convex cover and consists of the collector and a 130 litre enamelled tank. The double-walled plastic casing is highly permeable to solar radiation on one side and prevents heat losses on the other. A 2-kW electric heating element with an adjustable thermostat ensures a reliable hot water supply on cloudy days.
Photo: Stephanie Banse
The manufacturers of integrated storage collectors have placed their focus on the tourism and recreation sector. The compact systems can supply affordable and environmentally friendly energy to summer houses and cottages and even to mobile homes, caravans and boats. Other system advantages are the low weight of the collectors, their easy installation and low maintenance requirements. In addition, the passive system and the pumped PV-driven model do not need any external electricity supply.
This text was written by Stephanie Banse, a German journalist specialised in solar thermal technology. (banse(@)solrico.com)