A convergence of electricity and heat

Transcription

1 Solar thermal mostra Convegno expocomfort A convergence of electricity and heat Traditional solar water heaters, such as the one shown here at Nobel s stand, is seeing competition both from tank collectors and from DHW heat pumps and PV heating systems. photos (6): Jens-peter meyer the international heating technology trade fair in milan, mce, showcased a huge array of innovations for the whole house. alongside the classic heating systems were photovoltaics and e-mobility. The more plus-energy houses catch on and smart-home systems become ubiquitous, the less heating systems can be viewed as independent from the rest of home systems. This was nowhere more evident than at Mostra Convegno Expocomfort (MCE) held in Milan in mid-march. In addition to heating equipment providers, increasing numbers of companies from the photovoltaics and e-mobility segments presented their wares. The central news pavilion presented innovations for the whole house. Among them was a new product called REACT from the Swiss inverter manufacturer ABB, which is a combination of single phase PV inverter and battery-based storage system. The basic version of the lithium-ion system can store 2 kwh of PV power. The storage capacity can be boosted to 6 kwh by adding two additional battery modules (see also the Intersolar preview on page 40). ABB also offers a smart home controller, which it calls Mylos free@home. The solution offers users the convenience of controlling their complete heating and other home utility systems via smart phone. With battery storage systems, PV plant owners can significantly increase their own consumption of the power they generate. But they can also help by switching on electric consumers, such as air conditioners and washing machines in a targeted way when the sun is shining, and then convert excess PV power to heat with an immersion heating element or heat pump. These options are precisely the ones on offer from the energy manager Elios4you Pro Smart by 4-noks. The ZigBee standard can control up to four wireless power outlets and smart switches. Users can constantly monitor and control energy 84 Sun & Wind Energy 3/2016

2 flows in their homes with the Elios4you app. 4-noks is a brand of the Italian Astrel Group. The group also offers traditional heating applications. The Hottoh brand is specialised in controllers for pellet and other biomass boilers. Here too an application, AppFire, lets users keep constant tabs on their boilers. The app lets you know when your pellets are running low, for instance. The Astrel Group manufactures app-controlled room thermostats under its Rialto brand. The GWC energy manager by Higeco, an Italian firm, can also monitor PV plants and energy flows. While the Elios4you Pro Smart is designed for small systems with up to 50 kw of capacity, the GWC can monitor systems with several hundred kw of output. It displays the amount of energy consumed and the amount produced. The re-phasing section contains data on the relation between active and reactive power. This information helps minimise energy losses and reduces maintenance costs. Riello is re-launching solar thermal Marketing Manager Claudio Danelutto of Astrel Group shows how easy it is to operate the Elios4you Pro Smart energy manager with the accompanying app. The indispensable tool for craftsmen and technicians! With the HE-Check, the function of the pump and the signals of the controller can be checked quickly and easily. PWM signal 0-10 V signal Solar thermal was presented in a variety of ways at the trade show stands of the big Italian heating equipment companies. At Ferrule, visitors had to search for a long time to find a collector. Riello, on the other hand, prominently displayed its new collector series right in the centre of things. The new solar collectors will be available in the 1.8, 2.2 and 2.6 m 2 sizes. The height is identical in all three models, so that they can be installed next to each other in any configuration. The harp absorbers allow for parallel connection of fields up to 15 m long. Riello booth A Solar Edition 85

3 Solar thermal mostra Convegno expocomfort Sunerg has launched new PV modules featuring cells with four bus bars. bonds copper pipes to aluminium absorbers ultrasonically. The collector features glass with an antireflective coating. At just 60 mm, the collectors have a very slender profile. To achieve low thermal losses despite the thin rear-wall insulation, Riello uses convection limiters spaced about 40 cm apart along the collector s length of about two metres. Riello s solar water tanks are also new. Their special feature is that two solar tanks with sizes of between 220 and 550 litres can be connected in parallel with a connection set. That makes it easy to fit 1,100 litres of tank volume even in tight, narrow spaces. In the master-slave system, the master system is equipped with the controller. During installation, the installer simply enters the temperature difference (ΔT), explains Product Manager Gianluca Donini. The flow rate is then self-regulating. Ariston Thermo has also launched a new collector. The Kairos CF 2.0 RF harp collector, equipped with anti-reflective coated glass, complements the firm s existing meander collector. Lower pressure losses make it easier to adjust flow in harp collectors. Ariston Thermo sees this as a key advantage of this design.

4 As announced last year, the German heating equipment company Viessmann now offers a collector with an switching absorber coating. If the absorber temperature increases above 80 C the microstructure of the coating changes. As a a result, emission is increased and the stagnation temperature is limited. Rising popularity of tank collectors As an alternative to traditional solar water heaters, ever more tank collectors are coming onto the market. The Italian company Sunerg presented a new tank collector this year. Ati di Mariani, also from Italy, offers two variants of these compact solar thermal systems, which have a combined tank and collector. The Totem model is pillar-shaped. In the Discoterm model, the tank is housed in a tub-like structure with a transparent plastic cover. The current Discoterm holds 135 litres. A 200-litre version, which will not be any larger than the original will be launched next year. Nobel, a Greek company, presented a prototype of a tank collector in Milan. In the Filios, absorbers and tanks are separated. A PV powered pump circulates the heat medium in the solar circuit, transporting heat from the absorber to a heat exchanger in the tank developed specifically for this product. Like nearly everywhere else in Europe, the market situation for solar-thermal is anything but rosy in Italy. Just a few years ago, for instance, demand for large-scale systems for hotels was far greater than it is today that is how Ariston Thermo, at any rate. Domestic hot water heat pumps are increasingly giving smaller solar-thermal systems a run for their money. A new series of DHW heat pumps comes from the Italian storage tank specialist Boilernova. The HPV version has no heat exchanger, while the HPM variant features a bottom-mounted heat exchanger for a solar thermal connection, and the HPD version has an additional upper top-up heat exchanger. All three models are available in 220 and 280 litre versions. The tanks have a COP of 3.7 at an air temperature of 20 C. The controller can be activated externally to use surplus from a PV array. Boilernova also has a new tank for air-to-water heat pumps. The WBD-EBD is a combination of an 80-litre buffer tank and a domestic hot water tank with either 270 or 460 litre capacity. Calor Max90 is the new DHW heat pump from Sunerg. It can hold up to 90 litres of hot water. Sunerg is one of the few solar energy pioneers that still manufactures both photovoltaic and solar thermal systems. The company has extended the spectrum of its line of PV modules this year. The X-Style modules hold cells with 4 bus bars. Customers can choose between mono- and polycrystalline cells. The cells of these bifacial PV modules are active on both sides and can also convert light falling on the back of the cells into electricity. The bifacial cells also have four bus bars. Solar Edition

5 Solar thermal mostra Convegno expocomfort manufacturer of solar thermal controllers. The heating element is located in an external pump assembly. This has the advantage that the PV heating system can be fitted to practically any storage tank, even those not equipped with a flange for the heating element. Thanks to the pump s speed controller, a specified target temperature can always be charged to the tank to ensure that the layering is not lost in the storage tank. The heating element can thus make use of any excess PV power from 0 to 3 kw. The FlowSol E is available in a domestic hot water version and in another version for heating system buffer water. Pump assemblies are a speciality of Lovato from Italy. The T-Box is a heating circuit distributor with and integrated hydraulic separator. The new T-Box is some 50 % smaller than the company s previous device, says CEO Michele Lovato. It can distribute up to 80 kw of heating output over a maximum of three separate heating circuits. The thermostat-controlled T-Fast mini water station, which delivers up to 16 l/min to the tap is also new. It can be installed either on or inside a wall and contains a heat meter and a circulation unit. The SAT Dual water station for flats made by the Italian firm Ivar, contains two heat meters, one for domestic hot water and the other for heating-system water. The station draws heat from a district or central heating line, and then distributes it to a heating circuit and produces hot water. An expansion tank is also already integrated into the compact unit. Italy s Seitron has launched a new infrared CO 2 sensor. The device measures the CO 2 content of indoor air from 0 to 2000 ppm with an accuracy of ± 30 ppm. The manufacturer specifies a ten-year average service life for the device. Currently, the sensor can only operate independently. It cannot be integrated into a smart-home system yet The DHW heat pump from Boilernova can make use of excess PV power. Rusted up? Prevent it! WITH ANTIFROGEN HEAT TRANSFER FLUIDS. New pump assemblies generate or distribute heat In addition to the DHW heat pump, PV heating systems with electrical heating elements are becoming ever more popular. One such product is the FlowSol E by German company Resol, previously known as a A new generation of heat-transfer fluids for heat pumps Until now, most antifreeze fluids used in groundsource heat pumps and geothermal probes for heat-pump systems have had an ethylene or polypropylene glycol base. Ethylene glycol has the disadvantage of being toxic. Propylene glycol is far less dangerous to the environment but it has a much higher viscosity. Kilfrost, a British manufacturer of heat-transfer fluids, took advantage of MCE Milan to present a new generation of products that are non-toxic and have an even lower viscosity than ethylene glycol. Particularly at temperatures of -10 C and lower, the new fluid is significantly less viscous. That results in far less pressure loss in the system and saves electricity costs for driving pumps. The heat-transfer fluid Kilfrost Geo is made entirely from renewable raw materials. Even the additives used to prevent the corrosion of pipes are nontoxic. Kilfrost has completely eliminated the use of nitrates, nitrites, borates and heavy metals. According to Phil Gray, the Technical Head of the company s 88 Sun & Wind Energy 3/2016

6 INSTALL HEAT RESISTANCE Resol s Head of Marketing, Julia Pfeil, presents the new FlowSol E PV heating system. Special Fluids Division, Kilfrost Geo instead contains inhibitors also used in the cosmetics and food industries. Another new product is Kilfrost ALV, a heattransfer medium used in industrial cooling circuits, such as those found in breweries. This is also a lowviscosity fluid. In a medium-sized brewery, energy consumption for driving pumps was reduced by 38 % after the plant switched over to Kilfrost ALV, according to the manufacturer. Phil Gray believes that the savings could be as much as 50 % in larger facilities. Gray is tight-lipped about exactly which chemical substance is used in the new heat-transfer fluid. He will only say that it is a mixture of a number of different substances. Jens-Peter Meyer The flexible solution for temperatures up to 220 C. Feed and return pipes with an integrated sensor cable form a perfect unit which is pre-insulated with a hightech polyester insulation material and fast to assemble with quick-fitting couplings. DuoSolar 220 is the natural choice for professional installers. Performance, availability, ease of installation Install it. Trust it. Exhibitors from the e-mobility and photovoltaics sectors came out in surprising numbers in Milan. Tel.: info@armacell.com Solar Edition