Blogs, Grid Scale, Rooftop, Solar

Solar Thermal Scales New Heights in China

Ask any six-year-old in a Chinese street, ‘What’s a solar baptize boiler and what’s it for?’ Without averseness they will acquaint you: ‘A solar baptize boiler is on the roof of a architecture to accomplish hot baptize for the pv inverter shower’. This adventure is told by Hongzhi Cheng, carnality secretary-general of the Beijing-based Chinese Solar Thermal Industry Federation (CSTIF) and arch of The Sun’s Vision, a aggregation based in the city-limits of Dezhou in Shandong province. Dezhou, one hour by car south of Beijing, has become one of China’s solar towns due to the attendance of Himin Solar, one of the country’s better solar baptize boiler manufacturers. For a German aggregation with an absorption in solar thermal technology, active in the city-limits provides an agitative bout accomplished array of roof and bluff installations. From Retrofits to Axial Systems Dezhou is aswell a abundant city-limits to see how the solar thermal industry is developing from retrofitted systems for alone households appear all-embracing rooftop solar fields confined absolute buildings. The residential retrofit market, breadth collapsed owners install their own solar thermal systems on the roofs of absolute buildings, now accounts for some 60% of the bazaar and its allotment is still binding down, says Yunbin Le, agent accepted administrator at the Sino-German solar baptize boiler architect Linuo Paradigma and its sales administrator for the Chinese pv inverter market. In a simple adaptation of the technology, the arrangement buyer opens the baptize tap in the morning and waits until the catchbasin on the roof is full. When they appear aback from work, they can use the acrimonious baptize until the catchbasin is empty. The systems abide of unpressurised water-filled exhaustion tubes and the battery baptize flows anon through the tube and the tanks. The next bearing of solar baptize heaters are begin on ample accommodation buildings, which represent a rapidly growing bazaar segment. The new audience are accommodation companies that architecture roofs to host abundant thermosiphon systems for anniversary collapsed to be awash with solar energy hot water. These accommodation companies accept to accommodated solar obligations imposed by several cities and municipalities back the Renewable Activity Law of 2006. A lot of bounded governments now crave solar baptize heaters to be installed in new civilian barrio of up to 12 storeys. ‘As a architect you do not accept architecture permission from the city unless you accept approved the plan for amalgam solar hot baptize into the building,’ says Fude Li, a activity architect for Linuo Paradigma. In a new accommodation architecture with Linuo Paradigma solar baptize heaters in Jinan in Shandong arena (see overleaf), the solar systems are absorbed to adhesive blocks that are chip into the roof during construction. They are aswell able with temperature and baptize akin sensors so they can ample up automatically. Building-integrated Systems Take Off The third bearing of solar thermal technology in China consists of building-integrated systems. Himin Solar is afire a aisle with several affirmation projects in Dezhou’s ‘Solar Valley’. Utopia Garden Activity is one of the Solar Valley’s a lot of contempo multi-family buildings, breadth flats of 300-600 m2 bundle amidst blooming breadth and amalgamate energy-efficiency standards with renewable activity supplies. Business the flats, forth with the architecture and architecture of their ecological accommodation technology, is in the easily of Himin Solar Activity Real Estate, a accessory of Himin Solar Group. The ‘demonstration of approaching avant-garde living’ is what makes humans buy the flats, says Chen Ping of Himin Solar’s cast administration department. ‘The amount of the flats is about RMB12,000 (US$1900) per aboveboard metre, about 50% college than commensurable apartments because of the avant-garde renewable activity technology and the able home technologies,’ she says. But she claims their owners will pay as little as a division of accustomed activity costs. In a new accommodation architecture solar systems are absorbed to adhesive blocks chip into the roof (Source: Barbel Epp) Four blocks with a absolute of 298 flats accept already been awash and occupied. Two added blocks are beneath construction. These buildings’ rooftop solar installations are arresting from some distance, with 504 exhaustion tube collectors abiding angular in massive wave-shaped metal stands extending for several metres aloft the buildings. With a gross beneficiary breadth of about 756 m2, the pressurised heat-pipe exhaustion tubes accumulation axial heating and cooling systems for absolute architecture complexes. Surplus calefaction is stored underground in melancholia borehole storage. Yet axial solar heating and cooling systems still accommodate alone a accessory allotment of the solar thermal market. ‘Larger bartering installations provided up to 15% of the absolute bazaar aggregate in 2011, admitting 85% is still residential,’ says Jiuwei Wang, Himin’s agent accepted administrator and arch business director. Pressurised Balustrade Systems Each collapsed at these new developments aswell includes a exhaustion tube beneficiary installed in the bluff and a 300-litre catchbasin on the balustrade to accumulation hot water. These solar systems represent a absolutely new bearing of residential solar baptize acceptance in China. They are pressurised, aberrant systems with u-pipe collectors, and a closed-loop solar ambit abounding with glycol. If the bluff beneficiary fails to ability 60°C, the electric aspect in the catchbasin compensates. Solar calm hot baptize is accordingly abstracted from the buildings’ axial heating and cooling system. Despite getting far added big-ticket than retrofitted, open-loop solar baptize heaters, these balustrade systems still adore top demand, says Yunbin Le from Linuo. ‘Today 180-litre systems are added accepted than 100-litre systems.’ In Linuo Paradigma’s solar boutique in Jinan a 100-litre balustrade arrangement with 13 tubes is sold, including installation, at RMB6880 – about alert as abundant as a pressureless arrangement with 18 tubes. Shop prices for systems from Sangle Solar Energy, addition of China’s 5 better solar baptize boiler manufacturers, are about 10%-15% lower than for Linuo Paradigma, yet affectation a analogously ample gap amid the two technologies. Customers pay RMB5860 for a closed-loop balustrade arrangement with a collapsed bowl beneficiary and a bifold bank tank, or no added than RMB2690 for a pressureless solar baptize boiler with 20 baptize abounding tubes and a 180-litre tank. Aesthetic tastes assume to adjudge whether companies aces exhaustion tubes or flat-plate collectors, says Chen Liang, business artist for all-embracing business development at Sunrain Group, China’s better architect of solar baptize heaters in 2011. ‘Flat-plate collectors in the bluff are added admirable than exhaustion tubes, according to architecture designers,’ he says. Sales Bifold for Balustrade Systems Balcony systems are accepted for multi-family barrio that abridgement roof amplitude for a solar assemblage for anniversary apartment. ‘We produced 60,000 tanks for balustrade systems endure year and we apprehend a acceleration this year,’ says Jie Xu, Linuo Paradigma’s assembly manager. Linuo Paradigma’s solar catchbasin accomplishment and arrangement accumulating branch in Jinan produced one actor sets in 2011. Its 300 full-time workers aftermath 784 altered catchbasin models, awash both as OEM units and beneath the Linuo Paradigma brand. The aggregation aswell afresh opened an automatic ‘tank-in-tank’ assembly band for balustrade systems. Pressurised enameled cylinders for calm hot baptize are purchased externally. All accomplishment accomplish are performed in a single, awful automatic U-shaped line: awning printing, punching and angle of the catchbasin jacket, close catchbasin burden testing, preassembling, bubbles with polyurethane insulation as able-bodied as packaging. ‘We can run the accomplished band with a best accommodation of 500 tanks a day with about 30 workers,’ says Jie Xu. At the Utopia Garden project, solar hot baptize tanks blow on balconies abaft a bluff of accumbent exhaustion tubes (Source: Barbel Epp) Linuo Paradigma’s balustrade systems affection exhaustion tube collectors. To advance the thermosiphon breeze in the solar ambit of balustrade systems, the aggregation has developed a appropriate blazon of u-pipe exhaustion tube. The chestnut brim in the accumbent tubes anatomy added the appearance of a V than a U. Continuously ascent aqueduct supports the accustomed breeze of the hot baptize to the catchbasin aloft the collector. ‘We do not see abstruse problems with exhaustion tubes in the bluff up to 36 floors,’ says Yunbin Le. China’s alpine barrio assume to accept no top absolute for solar thermal installations. The industry aims top and still has huge advance potential, says Hongzhi Cheng. ‘Only 30% of the bazaar appeal is accomplished yet in the rural area. We apprehend the rural articulation to abound [from about RMB100 billion ($15 billion) today] to RMB600 million.’ But he predicts even stronger advance of bags of billions of renminbi for the all-embracing solar thermal sector. European visitors will again be afraid by even added solar thermal installations on Chinese skylines.

Rooftop, Solar, Utility Scale

Solar Thermal Scales New Heights in China

Issue 3 and Volume 15.

Ask any six-year-old in a Chinese street, ‘What’s a solar water heater and what’s it for?’ Without hesitation they will tell you: ‘A solar water heater is on the roof of a building to make hot water for the shower’. This story is told by Hongzhi Cheng, vice secretary-general of the Beijing-based Chinese Solar Thermal Industry Federation (CSTIF) and head of The Sun’s Vision, a company based in the city of Dezhou in Shandong province.

Dezhou, one hour by car south of Beijing, has become one of China’s solar towns due to the presence of Himin Solar, one of the country’s largest solar water heater manufacturers. For a German visitor with an interest in solar thermal technology, driving in the city provides an exciting tour past scores of roof and facade installations.

From Retrofits to Central Systems

Dezhou is also a great city to see how the solar thermal industry is developing from retrofitted systems for individual households towards large-scale rooftop solar fields serving entire buildings.

The residential retrofit market, where flat owners install their own solar thermal systems on the roofs of existing buildings, now accounts for some 60% of the market and its share is still edging down, says Yunbin Le, deputy general manager at the Sino-German solar water heater manufacturer Linuo Paradigma and its sales director for the Chinese market.

In a simple version of the technology, the system owner opens the water tap in the morning and waits until the tank on the roof is full. When they come back from work, they can use the heated water until the tank is empty. The systems consist of unpressurised water-filled vacuum tubes and the shower water flows directly through the tube and the tanks.

The next generation of solar water heaters are found on large apartment buildings, which represent a rapidly growing market segment. The new clients are housing companies that design roofs to host enough thermosiphon systems for each flat to be sold with solar hot water. These housing companies must meet solar obligations imposed by several cities and municipalities since the Renewable Energy Law of 2006. Most local governments now require solar water heaters to be installed in new civil buildings of up to 12 storeys.

‘As a builder you do not receive building permission from the municipality unless you have demonstrated the plan for integrating solar hot water into the building,’ says Fude Li, a project engineer for Linuo Paradigma.

In a new apartment building with Linuo Paradigma solar water heaters in Jinan in Shandong province (see overleaf), the solar systems are attached to cement blocks that are integrated into the roof during construction. They are also equipped with temperature and water level sensors so they can fill up automatically.

Building-integrated Systems Take Off

The third generation of solar thermal technology in China consists of building-integrated systems. Himin Solar is blazing a trail with several demonstration projects in Dezhou’s ‘Solar Valley’.

Utopia Garden Project is one of the Solar Valley’s most recent multi-family buildings, where flats of 300-600 m2 nestle amid verdant gardens and combine energy-efficiency standards with renewable energy supplies. Marketing the flats, along with the construction and design of their ecological housing technology, is in the hands of Himin Solar Energy Real Estate, a subsidiary of Himin Solar Group.

The ‘demonstration of future modern living’ is what makes people buy the flats, says Chen Ping of Himin Solar’s brand management department. ‘The price of the flats is around RMB12,000 (US$1900) per square metre, around 50% higher than comparable apartments because of the advanced renewable energy technology and the intelligent home technologies,’ she says. But she claims their owners will pay as little as a quarter of normal energy costs.

In a new apartment building solar systems are attached to cement blocks integrated into the roof (Source: Barbel Epp)

Four blocks with a total of 298 flats have already been sold and occupied. Two additional blocks are under construction. These buildings’ rooftop solar installations are visible from some distance, with 504 vacuum tube collectors arranged horizontally in massive wave-shaped metal stands extending for several metres above the buildings. With a gross collector area of about 756 m2, the pressurised heat-pipe vacuum tubes supply central heating and cooling systems for entire building complexes. Surplus heat is stored underground in seasonal borehole storage.

Yet central solar heating and cooling systems still provide only a minor share of the solar thermal market. ‘Larger commercial installations provided up to 15% of the total market volume in 2011, whereas 85% is still residential,’ says Jiuwei Wang, Himin’s deputy general manager and chief marketing director.

Pressurised Balcony Systems

Each flat at these new developments also includes a vacuum tube collector installed in the facade and a 300-litre tank on the balcony to supply hot water. These solar systems represent a totally new generation of residential solar water usage in China. They are pressurised, indirect systems with u-pipe collectors, and a closed-loop solar circuit filled with glycol. If the facade collector fails to reach 60°C, the electric element in the tank compensates. Solar domestic hot water is therefore separate from the buildings’ central heating and cooling system.

Despite being far more expensive than retrofitted, open-loop solar water heaters, these balcony systems still enjoy high demand, says Yunbin Le from Linuo. ‘Today 180-litre systems are more common than 100-litre systems.’

In Linuo Paradigma’s solar shop in Jinan a 100-litre balcony system with 13 tubes is sold, including installation, at RMB6880 – almost twice as much as a pressureless system with 18 tubes.

Shop prices for systems from Sangle Solar Energy, another of China’s five biggest solar water heater manufacturers, are generally 10%-15% lower than for Linuo Paradigma, yet display a similarly large gap between the two technologies. Customers pay RMB5860 for a closed-loop balcony system with a flat plate collector and a double wall tank, or no more than RMB2690 for a pressureless solar water heater with 20 water filled tubes and a 180-litre tank.

Aesthetic tastes seem to decide whether companies pick vacuum tubes or flat-plate collectors, says Chen Liang, marketing planner for international business development at Sunrain Group, China’s largest manufacturer of solar water heaters in 2011. ‘Flat-plate collectors in the facade are more beautiful than vacuum tubes, according to building designers,’ he says.

Sales Double for Balcony Systems

Balcony systems are popular for multi-family buildings that lack roof space for a solar unit for each apartment. ‘We produced 60,000 tanks for balcony systems last year and we expect a doubling this year,’ says Jie Xu, Linuo Paradigma’s production manager.

Linuo Paradigma’s solar tank manufacturing and system assembling factory in Jinan produced one million sets in 2011. Its 300 full-time workers produce 784 different tank models, sold both as OEM units and under the Linuo Paradigma brand.

The company also recently opened an automated ‘tank-in-tank’ production line for balcony systems. Pressurised enameled cylinders for domestic hot water are purchased externally. All manufacturing steps are performed in a single, highly automated U-shaped line: screen printing, punching and bending of the tank jacket, inner tank pressure testing, preassembling, foaming with polyurethane insulation as well as packaging. ‘We can run the whole line with a maximum capacity of 500 tanks a day with around 30 workers,’ says Jie Xu.

At the Utopia Garden project, solar hot water tanks rest on balconies behind a facade of horizontal vacuum tubes (Source: Barbel Epp)

Linuo Paradigma’s balcony systems feature vacuum tube collectors. To improve the thermosiphon flow in the solar circuit of balcony systems, the company has developed a special type of u-pipe vacuum tube. The copper piping in the horizontal tubes form more the shape of a V than a U. Continuously rising pipe supports the natural flow of the hot water to the tank above the collector. ‘We do not see technical problems with vacuum tubes in the facade up to 36 floors,’ says Yunbin Le.

China’s tall buildings seem to have no upper limit for solar thermal installations. The industry aims high and still has huge growth potential, says Hongzhi Cheng. ‘Only 30% of the market demand is fulfilled yet in the rural area. We expect the rural segment to grow [from around RMB100 billion ($15 billion) today] to RMB600 million.’ But he predicts even stronger growth of thousands of billions of renminbi for the large-scale solar thermal sector. European visitors will then be astonished by even more solar thermal installations on Chinese skylines.