Page 150 - Solar Power in Building Design The Engineer's Complete Design Resource

120 SOLAR POWER GENERATION PROJECT IMPLEMENTATION

Project design criteria The residential power demand for a single-family dwelling
involves specific limits of energy use allocations for area lighting, kitchen appliances,
laundry, and air-conditioning systems. For example, the allowed maximum lighting
power consumption is 3 W per square foot of habitable area. The laundry load allowed
is 1500 W for the washer and dryer.
The first 3000 W of the total combined lighting and laundry loads are counted at
100 percent, and the balance is applied at 35 percent. The total appliance loads, when
there are more than five appliances, are also derated by 25 percent. Air conditioning
and other loads such as the pool, sauna, and Jacuzzi are applied at their 100 percent
value.
The demand load calculation of the 1400-ft residential dwelling shown in Figure 5.1
2
indicates a continuous demand load of about 3000 W/h. If it is assumed that the resi-
dence is fully occupied and is in use for 12 hours a day, the total daily demand load

Figure 5.1 Roof-mount PV array layout, Reed residence,
Palm Springs, California.