“The trend here at the fair is clear: integration of solar components,” said Michele Di Marino, export manager for The Ferroli Group (San Bonifacio, Italy; www.gruppoferroli.com). “For instance, our Ferroli Ecoconcept ST: two condenser combiboilers (25 and 35 kW) with a solar panel connection. They have a three-star DHW comfort marking, a four-star energy marking, 25 liters of dynamic DHW storage, and the unique Ferroli aluminum heat exchanger, which also incorporates the condensing function. The Ecoconcept Tech models (25 and 35 kW) offer fewer features at a lower price point but still have the condenser technique and the solar power connection. We designed these models mainly for large projects.”
On the floor of the new Fiera Milano Exhibition Centre in the midst of the 2008 Mostra Convegno trade fair for the European HVAC industry, the U.S. banking crisis seemed far away. This was due in part to the sunny weather, but also because of a good business climate in general.
But it is the European business climate that’s strong, not so much the Italian. Total exhibitor count was down slightly (from 2750 in 2006 to 2700 in 2008), but the number of foreign exhibitors was up 8% to 600. Foreign visitors were up 17%. The official press message explains that the reduction in the Italian visitor count stems from “static conditions of our national economy.”
The majority of exhibitors are heating and cooling companies, but there are also energy companies (solar, insulation, biofuels, and cogeneration) and water products companies (plumbing and water treatment). The buzzwords in Milan: solar integration, meaning the integration of solar panels with boilers and water heaters.
As one exhibitor said: “No new devices, but they all show boilers having a standard solar panel connection.” Before, most boilers required a separate control unit for the solar panel for domestic hot water (DHW).
And indeed, all the heating manufacturers presented integrated boilers. Even some of the air-conditioning OEMs joined in. The solar panel used in the application is generally the flat-panel type having direct water flow, and not the more expensive vacuum-tube type.
The trend is driven by increased interest and by new regulations in Italy and Spain requiring new buildings to have renewable sources for DHW production.
“These new regulations bring new life into some suffering Western European markets,” Michele Di Marino, export manager for Ferroli, tells APPLIANCE magazine. “Many consumers do talk a lot about ecology but are not willing to invest themselves, and rely on subsidies. Sadly, these subsidies differ per country; there is not much EU-wide standardization, which is difficult for the manufacturers. In Italy there are even differences between North and South. Luckily the market in Eastern Europe is very good, with double-digit growth figures.”
Ferroli Group is the second-largest Italian heating OEM, after MTS, and sixth-largest in Europe (after BBT, Vaillant, Viessmann, and Baxi). Revenues were €622 million in the most recent fiscal year (2005–2006) and the company has a staff of 3000. Unlike some competitors, they have a wide product range in commercial and residential heating, as well as DHW.
Ferroli sees its in-house engineering expertise and ability to innovate as important strengths. “Our company has a strict policy of in-house design and manufacturing,” Di Marino said. “We buy very few components, and we have the biggest test chamber in Italy, which also does third-party testing. So we are sure of our quality, and our in-house expertise allows us to deliver custom-made solutions for commercial products.”
MTS Group exhibited solar panel technology in which the solar panel and the boiler share the same control unit. MTS acquired the Swiss company Thermogamma in 2007 and exhibited its new heat pump line at Mostra, including a new model called Nuos. “Nuos is a sanitary water heat pump that creates a new standard of efficiency,” said Mario Salari, marketing manager, Italy and overseas. Other new products include the Genus HP condensing boiler. MTS’s Ariston brand offers integrated solutions with all the fittings required for modular installations in order to meet the needs for heating systems for apartment buildings. In solar systems, the new MTS flat-panel Kairos 2.5 was introduced with a larger collector surface to absorb more heat.
Legislation Changes Italian Markets
Paolo Beolchi, marketing manager for Junkers, a Bosch Thermotechnik (www.bosch-thermotechnology.com) brand, explained how the market in Italy is changing as a result of new laws requiring that a certain percentage of DHW be produced with renewable energy in new construction. “There will be a strong trend in new buildings towards centralized production of heating and DHW because it is easier to connect with solar panels.”
Additionally, for the last year there have been tax incentives in place, providing discounts as high as 55% for replacement of old boilers with condensing boilers and/or installing solar panels on existing buildings.
Key to optimized solar water-heating technology is the control system. “The Bosch brands now offer a unique and patented control software algorithm called SolarInside,” Beolchi said. “The control unit stores data on outside temperature and sun hours and uses this to predict solar power per day.” The control’s prediction of sunlight and outside temperatures means it can adjust operation for better efficiency. “This can be used for DHW as well as room heating, and it can deliver savings of up to 15%.”
Bosch Thermotechnik developed the SolarInside control software algorithm, which stores data on sunlight hours and outdoor temperatures to predict conditions and optimize panel operation.
Engineering High Absorptance/Low Emittance
Chromagen Solar Energy Systems (www.chromagen.biz) is based in Israel, one of the world’s only mature markets for heat-collecting solar panels. Solar heat collectors were mandated in Israel in 1980 and now about 85% of homes have them. Chromagen has been around even longer, since 1962, and today manufactures boilers and flat-panel-type solar panels.
One benefit the company has been able to demonstrate in that time is the panels’ longevity. “Many times they last as long as 30 years, whereas the more efficient vacuum-tube panels might lose their vacuum much earlier,” engineer Micky Carmel told APPLIANCE during Mostra Convegno.
“The most important criteria [of the solar panels] are the absorptance factor (a), indicating the amount of absorbed irradiation, and the emittance factor (e), indicating how much of the absorbed heat is radiated back into the environment.” Low emittance is achieved with the sputtering coating technique, in which the coating is applied in a vacuum chamber. Gas, containing metal particles, is introduced to the vacuum chamber to apply an ultrathin surface top layer on the panel. It’s a process used in the semiconductor industry for insulation glass, and for applying the reflective layer on CDs and DVDs. In solar panels it helps Chromagen achieve an e-factor as low as 5%.
As one would guess, sputtering is expensive. A less costly black- chrome coating process has an 11% e-factor, and some specialized paints will have a 40% e-factor. Untreated panel reflects about 80%, and in some climates, Carmel said, even this low efficiency is sufficient for the application.
Transmittance is the most important factor in a glass panel. Simple glass with a thickness of 3 mm transmits approximately 88% of the solar irradiation. “It is common to use a low-iron-content glass that transmits 91–92% of the solar irradiation,” Carmel said.
New requirements in Spain and elsewhere for renewable energy DHW sources are spurring the market for solar panels. “Still, the market is not really exploding like the industry had hoped,” Carmel said. “For Europe, the growth is 10 to 15%—where we expected around 30%.
This is in part because current DHW solar panels are not addressing the biggest problem—heat. Getting effective room heating out of solar panels requires a 90°C input temperature, a technology that is much more difficult to achieve in mass-marketed solar collectors.
Made in Brussels
While the heating OEMs attracted the most attention at Mostra, several air-conditioning producers were on hand with large-scale exhibitions reflecting an upbeat mood. Among them was Daikin In-dustries (www.daikin.com), the Osaka-based HVAC giant with several European business units. 2007 was a good year in Europe for Daikin. Daniele Legranzini, market manager, explained that the company did good business in 2003 and 2004, followed by two down years. But in 2007 business improved, and the company is optimistic about 2008.
“Of course A/C demand follows the weather conditions here in Europe, and it is a fluctuating market,” Legranzini said. “Typically, the consumer waits until the end of June to decide (on an air-conditioner purchase).”
New from Daikin is the Altherma system for powering indoor heating and a DHW tank by using an air-source heat pump. “The extracted heat is transferred via the refrigerant circuit to the indoor, so-called hydro-box,” Legranzini said. “This box transfers the heat in the refrigerant to the water circulated in the central heating radiators, underfloor heating system, and sanitary hot water tank.”
“This is a new product, designed and built in Europe in our Brussels facilities,” Legranzini explained. “An integrated solar panel can be connected through a solar kit, and then controlled by the central control unit.”