system accomplished
System Accomplished is a new SOLAR TODA Y feature, focusing on unique design or installation problems and how they
were solved. If you have solved a difficult installation problem, we want to hear about it. Email smasia@solartoday.org.
THE UNIVERSITy OF ARkaNSAS/FAyEttEVILLE IN OCTOBER COMMISSIONED AN array of 48 solar hot
water collectors on the roof of the Health, Physical Education and Recreation Building (HPER), to provide more than
half of the energy used yearly to heat the indoor Olympic-sized swimming pool. The SunEarth EC40 modules, total-
ing 1,920 square feet (189 square meters), harvest more than 2 million Btu per day to provide all of the heat for the
730,000-gallon pool during the summer and to preheat water in the winter, to 80°F ( 27°C). The university estimates the
system will save about $4,000 annually in natural gas at today’s prices, and $10,000 annually if gas prices re-
turn to 2008 levels. Sun City Solar Commercial Energy of Springdale, Ark., designed and installed the system
as a subcontractor for Energy Systems Group.
The major challenge was the distance from the roof to the heat exchanger in the basement. The primary
circuit runs about 40 feet ( 12 meters) down and 250 feet (76 m) horizontally. According to John Gerrard,
general manager at Sun City, the company used about 1,000 feet (305 m) of 3-inch ( 7. 5 cm) copper pipe
for the feed and return lines and to connect the eight banks of collectors into the feed and return lines. The
copper is insulated with ¾-inch (2-cm) slip-on foam sheathing, which was painted with an antiweathering
elastomeric coating. The heat exchanger is an Alliance AIC titanium unit. A Versaflo TP inline single-stage
pump moves the glycol mixture at up to 150 gallons per minute ( 9. 5 liters per second) at 40 to 70 psi ( 2. 8 to 4. 8 bar).
Last year the HPER Building pool had a total of 55,000 users. In addition to university students, faculty and staff, the
pool is the site of collegiate and high school swim and dive meets, it serves as a practice facility for several swim clubs and
teams, and it is used for swimming instruction, group exercise programs and entertainment, such as the popular “dive-in”
movies at the pool. — SE Th MASIA
Pool-Heating
Project Resolves
Distance Issue
