Page 319 - Handbook of Energy Engineering Calculations

shows the minimum spacing to use between collector rows, based on the
latitude of the installation and collector tilt.

4. Sketch the system layout
Figure 6 shows the key components of a solar system using fiat-plate
collectors to capture solar radiation. The arrangement provides for heating,

cooling, and hot-water production in this industrial building with sunlight
supplying about 60 percent of the energy needed to meet these loads—a
typical percentage for solar systems.

FIGURE 6 Key components of a solar-energy system using flat-

plate collectors. (Power.)

For this layout, water circulating in the rooftop collector modules is heated
to 160°F (71.1°C) to 215°F (101.7°C). The total collector area is 10.000 ft 2
2
(920 m ). Excess heated hot water not needed for space heating or cooling or
for domestic water is directed to four 6000-gal (22.740-L) tanks for short-
term energy storage. Conventional heating equipment provides the hot water
needed for heating and cooling during excessive periods of cloudy weather.

During a period of 3 hours around noon on a clear day, the heat output of the
collectors is about 2 million Btu/h (586 kW), with an efficiency of about 50
percent at these conditions.