During the last seven years, a group of scientists has monitored selected large solar thermal installations in Austria on behalf of the Austrian Climate and Energy Fund. The gathered data confirms that these plants have been reliable and produce satisfactory yields. Particularly the new generation of large-scale medium-temperature collectors either with a foil or with a second glass cover shows remarkable results in district heating use. The 2,490 m² solar field (see photo) which has fed heat into the district heating network of Graz, Austria, reached a yield of 489 kWh/m².
On 24 November, the fifth Solar Heat Switzerland (Solarwärme Schweiz) conference organised by the solar industry association Swissolar, the building services association suissetec and the Federal Office of Energy was held in Lucerne, Switzerland. As 2017 funding for solar heat incentives remains in doubt in several cantons and the priorities of the country´s energy policy haven’t been announced yet, the market outlook for solar thermal has not been very encouraging. But there seems to be a ray of hope in the form of low-temperature collectors for borehole regeneration and solar district heating. Click here to download the German-language presentations from the conference.
In spring 2015, Germany´s Federal Office for Economic Affairs and Export Control (BAFA) introduced a performance-based incentive for solar heating as an alternative to the scheme offering incentives based on collector area. Recently published statistics have shown the new programme to grant higher financial support for about one-third of the currently funded projects. The others still receive funding from the previously established scheme.
The 4th International Solar District Heating (SDH) Conference, which had been organised under the auspices of Horizon 2020 project SDHp2m…from Policy to Market on 21/22 September 2016 in Denmark, showed the importance of analysing real-life monitoring data from European SDH plants, with one conference session (Advanced SDH systems II) dedicated exclusively to the topic. These kinds of comparisons enable an understanding of the actual performance of such large collector fields and offer an opportunity for optimising power output and for creating best-practice examples of new plants. For example, the chart displays ten years’ worth of monitoring data from the German plant in Crailsheim, which has met solar yield expectations.
Source: Attached SDH conference presentation from ITW
At present, the Danish turnkey supplier of concentrating solar systems, Aalborg CSP, has two more large projects under construction. Both installations – one for Danish district heating company Brønderslev Forsyning and one for Australian vegetables producer Sundrop Farms – cover electricity and heat demand at their sites. Yet another first-of-its-kind project was inaugurated in August 2015 in the Danish village of Tårs (see photo), 30 km north of Aalborg. It entailed 4,039 m² of parabolic trough collectors and a preheating flat plate collector field of 5,972 m². Simulations have pointed to a 31 % coverage of annual heat demand even without seasonal storage, since overheating in summer can be avoided by moving the parabolic trough collectors out of focus. Aalborg CSP is an experienced planner of steam and boiler systems and has been offering concentrating solar solutions since 2007.
“Large-scale solar thermal systems in the GW range – an insignificant niche market or the future for solar thermal?” was the official title of a panel discussion at the Gleisdorf Solar conference in Austria in early May. The most important question was: What will be next for the planned 350 MWth solar district heating system called Big Solar in the Austrian city of Graz? “The challenge was to adapt the Danish district heating solutions to Austrian conditions,” emphasised the project’s initiator, Christian Holter (right), Managing Director of S.O.L.I.D. Meanwhile, Christian Stadler (left), Managing Director of one of Arcon-Sunmark’s subsidiaries, Arcon-Sunmark Germany & Austria, represented the company that has stated his own interest in realising Big Solar.
The first and so far unique solar district heating plant in Italy completed its first year in operation in mid-May this year. According to metering by the operator of the 990 m² collector field, utility Varese Risorse, output was significantly higher than expected. The chart shows the total output measured over almost 12 months: It was 13 % higher than the target figure. The solar district heating plant was developed and installed by a newly founded Italian company, SDH Energy, which also guaranteed the solar yield (red line).
According to the ISOL Index by solrico and market data from the industry association Austria Solar, the solar thermal industry is heading into another year of declining markets. Low oil prices and corresponding campaigns of the fossil heating industry have had a substantial impact on this renewable technology. The banner shows the slogan “Heizen mit Öl – das zahlt sich aus” (The Benefits of Using Oil to Heat Your Home) on the website of the Austrian mineral oil industry, which offers grants of EUR 2,500 for the installation of a condensing oil boiler in a single-family building. Austria Solar has also criticised the reduction in the renewable budget of the Austrian Climate and Energy Fund as well as the complicated incentive scheme rules throughout the states. The large-scale project market is what keeps the industry alive.
The latest statistics of Conto Termico in Italy show that the national incentive scheme has still not been used enough: As of 1 January 2016, it had supported only 62 solar thermal plants for public buildings, while the private sector figure was 10,634. Assuming an average plant size of 7 m², as estimated by Gestore dei Servizi Energetici (GSE), this corresponds to a total subsidised collector area of 75,000 m² – a fairly low result over the 30 months of the scheme. The subsidy volume for solar thermal now amounts to about EUR 27.5 million, around half of the total incentives which have so far been distributed by Conto Termico. This is again a rather small figure compared to an originally planned budget of EUR 900 million. GSE, the state-owned administrator of Conto Termico, has therefore modified the scheme rules.
The publication of the EU Strategy on Heating and Cooling (Heat Strategy) is now scheduled for February 2016, when it will be published as part of the winter (legislative) package comprising a revised Security of Gas Supply Regulation and an EU strategy for liquefied natural gas. The Heat Strategy was supposed to be already out on 18 November 2015. The consultation process is now over and the ENER C3 unit of the Directorate General (DG) of Energy is drafting the final version. The photos show the two most important heads of European energy strategies, both with a five-year term up to 2019: Maroš Šefčovič from Slovakia, Vice-President of the European Commission and in charge of the Energy Union (left), and Miguel Arias Cañete from Spain, the commissioner for Energy and Climate Action.