PVT Big Solar projects
 PVT Big Solar projects for industrial clients in Austria

PVT Big Solar projects for industrial clients in Austria

The Austrian planning team Simona Alexe – greenixcloud is now developing PVT Big Solar projects for industrial clients. Big Solar refers to solar heat systems that store surplus solar energy from the summer in seasonal storage to cover energy needs in winter. The term has previously been used for large collector fields in solar district heating projects, but will now also be applied to PVT fields and industrial heat consumers. High-temperature heat pumps play a special role in using the stored solar heat and increase its temperature to that required by the manufacturing process. The Austrian institute AEE INTEC was also involved in developing this concept and created the chart above to showcase the path for decarbonising industrial processes between 70 and 150 °C. The Austrian Climate and Energy Fund subsidised the first feasibility study to apply the concept for an Austrian textile producer.

“The parallel production of electricity and heat from a PVT field is more efficient than the separate installation of PV and collectors”, explained greenixcloud’s Project Manager Heinz Peter Stoessel. He was invited to be a speaker at two events in February, where he introduced the PVT Big Solar concept: first at a half-day workshop that took place at Campus Pinkafeld in eastern Austria and then during an online business webinar titled Decarbonising Vienna.

PVT Big Solar projects
The mail distribution centre in Pernitz, Austria, with a PVT field on the roof and a polymer register which is placed on the ground and covered with the concrete of the ground floor. Photos: Simona Alexe – greenixcloud

Greenixcloud gained its initial experience with PVT when planning the new mail distribution centre in Pernitz, south of Vienna, together with the German company Building Energy Solutions. 60 PVT panels on the roof together with a one-layer, ground-based polymer piping register totalling 490 m2 provide heat for a brine heat pump. This is the main heat source that keeps the mail distribution centre at around 20 °C indoor temperature and is also used for unfreezing the ramps to the centre. The solar electricity is also provided to 10 electric car charging stations.

The energy supply concept follows the Zero Emission Building Design that Greenixcloud uses for all its projects. Averaged over the year, the building consumes the same amount of electricity for the heat pump and other appliances that is gained from the PVT field. Within the subsidy scheme of the Climate and Energy Fund, this project was chosen for detailed monitoring, which will start in the first half of 2023.

PVT field 60 PVT collectors of the type IS 2 Power Pro
Type of PVT collector Volther Excell PVT from Solimpeks, Turkey
PV capacity of PVT field 19.5 kWp (60 * 325 Wp)
Size of the PV field 101 m2
Type of heat pump IS WP Prime Solo from Building Energy Solutions
Range of temperature of heat source for heat pump -10 to +15 °C
Capacity of heat pump (0/35) 25.3 kW
Size of ground-based polymer piping register 490 m2

Key figures for the PVT heat pump system at Pernitz in operation since October 2020. The heat from the insulated PVT collectors is stored in the ground below the building to be used in winter. The ground-based register is dimensioned in such a way that it never falls below 0 °C.
Source: Simona Alexe – greenixcloud / Building Energy Solutions

PVT Big Solar for Austrian textile producer

“In the next projects for industrial clients we would like to adapt the PVT heat pump system to meet heat needs up to 130 °C”, announced Stoessel during the presentations. He described the results of the feasibility study for the textile producer. A 17,000 m2 PVT field will be operated in a loop with seasonal storage of 20,000 m3. Two high-temperature heat pumps of 1.4 MW each will provide steam and hot water to the factory.

The operation of the new renewable PVT-based process heat delivery system for the textile factory will be supported by a conversion of the supply concept from a steam network to a hot water system. Steam will only be used where absolutely necessary for production reasons.

Sunmaxx PVT ordered a PVT line with 50 MW annual production capacity

Stoessel is negotiating with the newly founded German PVT collector manufacturer Sunmaxx PVT. “Sunmaxx has a fairly automated production facility backed-up by knowledge from the automotive industry. This makes them an attractive partner for the large-scale industrial heat projects we are currently elaborating,” said Stoessel.

Sunmaxx PVT was founded in 2021 by Dr Wilhelm Stein, who has a background as a cleantech entrepreneur and solar industry expert. The foundation of the company was supported by Mahle Group, an automotive supplier from southern Germany with 72,000 employees.

The new PVT element consists of a standard photovoltaic panel to which an aluminium absorber is attached. The thermal absorber is produced and delivered by Mahle, based on a process used in battery cooling for electric cars. “We have found a solution for combining thermal absorber and PV module in a reliable, cost-efficient and mass-producible way” explained Dr Stein. The machinery for the first production line (50 MW) for PVT collectors has been ordered, according to Stein. The PVT collectors are currently being tested at Fraunhofer ISE, Germany. The Solar Keymark certificate is expected later this year.

Mahle is investor, supplier and client at the same time

Stein also emphasised the fact that Mahle is very interested in installing Sunmaxx PVT modules on its own production facilities. A first large-scale application for the Sunmaxx panels could come about at a Mahle site in Southern Germany. The production site with around 17,000 m2 of factory space is currently heated with natural gas. As an alternative heating system, a feasibility study analysed the combination of PVT elements and boreholes as two heat sources for brine heat pumps. Stein emphasized the fact that a significant amount of drilling metres can be saved by using PVT elements and thus “achieve significantly better profitability for the customer”.

Websites of organisations mentioned in this news article:
Greenixcloud: https://www.firmenabc.at/simona-alexe_OPWR
Building Energy Solutions: https://www.bes-eu.com/
Sunmaxx PVT: https://sunmaxx-pvt.com/en/
Climate and Energy Fund: https://www.klimafonds.gv.at/
Mahle Group: https://www.mahle.com/en/
AEE INTEC: https://www.aee-intec.at/
Solimpeks: https://solimpeks.com/

Bärbel Epp

Bärbel Epp is Founder and Director of the German communication and market research agency solrico and editor-in-chief of solarthermalworld.org