No abstract

In summer of 1992, we monitored peak power and cooling energy savings from shade trees in two houses in Sacramento, CA. The collected data include airconditioning electricity use, indoor and outdoor dry bulb temperatures and humidities, roof and ceiling surface temperatures, inside and outside wall temperatures, insolation, and wind speed and direction. Shade trees at the two monitored houses yielded seasonal cooling energy savings of 30%, corresponding to an average daily savings of 3.6 and 4.8 kWh/ d. Peak demand savings for the same houses were 0.6 and 0.8 kW (about 27% savings in one house and 42% in the other). The monitored houses were modeled with the DOE-2.1E simulation program. The simulation results underestimated the cooling energy savings and peak power reductions by as much as twofold.

No abstract

A network of 23 weather stations was used to detect existing oases in Southern California. Four stations, separated from one another by 15 -25 miles (24 -40 km), were closely examined. Data were strongly affected by the distance of the stations from the Pacific Ocean. This and other city-scale effects made the network inadequate for detection of urban oases. We also conducted traverse measurements of temperature and humidity in the Whittier Narrows Recreation Area in Los Angeies County on Sept. 8-10, 1993. Near-surface air temperatures over vegetated areas were 1 -2°C lower than background air temperatures. We estimate that vegetation may lower urban temperatures by 1°C, while the establishment of vegetative canopies may lower local temperatures by an additional 2°C. An increase in vegetation in residential neighborhoods may reduce peak loads in the Los Angeles area by 0.3 GW, and reduce energy consumption by 0.2 BkWh/year, saving $20 million annually. Large additional savings would result from regional cooling. t This workwassupportedby theCaliforniaInstitutefor EnergyEfficiency(CW_.E) throughtheU. S. Department of Energy,undercontractDE-AC0376SF00098. _:Presentaffiliation:CapitalEnvironmental Eng. Corp.,Taipei, Taiwan,R.O.C.