Ole Pilgaard, Heliodyne
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Founded in 1976, Heliodyne is the oldest continuously operating solar water heating equipment manufacturer in the US. Ole Pilgaard has served as president of Heliodyne since 2007. Previously, Ole was head of the solar energy division for VELUX. He also served as president of the European Solar Industry Federation, director of the European Energy Council and chairman for the European Solar Thermal Conference. Ole has been on the board of the Solar Rating & Certification Corporation (SRCC) since 2008 and currently serves as chair of the SRCC industry group. He holds degrees in mechanical engineering from the Engineering College of Copenhagen and in international economics and trade from Copenhagen Business School.
SP: The European solar thermal (ST) industry is robust compared to the US market. What are the key factors that account for this difference?
OP: Issues of energy security in the European Union became apparent much earlier in Europe than in the US, so politicians have pushed renewable energy for much longer. Furthermore, the European solar thermal industry did not go through the turmoil that occurred in the US after the tax credits were abolished back in the ’80s. Consequently, the solar thermal market has experienced a more consistent and uninterrupted evolution in Europe. There is a much higher rate of awareness about solar thermal, and the ongoing demand has created a solid work force.
SP: Based on your experience in the European market, did you implement any significant changes in Heliodyne’s direction or product lines when you took the helm?
OP: The most apparent changes were made in moving the company focus away from merely manufacturing collectors and forcing installers to piece a system together. We moved toward a system approach in which all the components are plug-and-play and easy to install. As more developed, Europeanmanufactured equipment was being introduced to the US market, it was important to improve Heliodyne’s equipment design and also make a differentiated product platform. Furthermore, it was important to profile Heliodyne as a reliable supplier with a 35-year track record of supplying quality products in the US.
SP: Drainback system design for freeze protection is not as popular in Europe as it is in the US. What is the source of this fundamental variation in design philosophy?
OP: The European solar thermal industry developed faster in the northern countries, like Germany and Austria, where freeze protection is more of an issue than stagnation. Some malfunctioning drainback systems received bad publicity in Europe when solar thermal grew into the mainstream contractor business. As a result, it became more apparent that drainback systems are extremely sensitive to correct installation. The European solar thermal technology platform therefore developed in the direction of fully flooded glycol systems, which are more reliable than drainback systems and less sensitive to correct installation.
SP: Why is serpentine-tube collector construction popular with European flat-plate manufacturers while US manufacturers, including Heliodyne, exclusively use a grid-type, or harp, absorber construction?
OP: It’s really quite simple. The serpentine concept, contrary to the harp design, is based on one riser and consequently has a lot fewer joints to braze. It’s therefore cheaper to produce. US manufacturers have been hesitant to move to serpentine collector design because of the larger pressure drop inherent in this design approach and the resulting decrease in flow rates and performance because the collectors operate at a higher delta T.
SP: Lower-priced, Asian manufactured twin-tube evacuated heat pipe systems are gaining traction in the US market. Has this trend influenced Heliodyne’s long- or short-term business strategies?
OP: Heliodyne is monitoring the development of the tube business in the US very carefully, but so far we have no desire to enter that market. This is primarily because we believe twintube technology is not suitable for the general US ST market. The technology creates issues with stagnation, cost and ease of installation—and it is more vulnerable to weather events such as hail.