6 Evaporative Air-Conditioning: Applications for Environmentally Friendly Cooling Table 1.1. Vapor-Compression versus Evaporative Air-Conditioning Basic characteristics Vapor compression AC Evaporative AC Coolant CFCs/HFCs Water Production residential coolers Small and large scale Small and large scale Sensitivity to humidity for Applicable in all climate types Applicable in dry hot climates comfort cooling applications for comfort cooling Ventilation (indoor air quality) 20% outside air 100% outside air Energy use in a typical residential 1,000 kWh/yr 350 kWh/yr air conditioner for a 100 m 3 room. Investment for a residential cooler Developed country Developed country US$1,000-1,600 US$200-700 Less developed country Less developed country US$600-1,400 US$60-300 Maintenance Change filters every 2 years Annual pad change for aspen sump coat every 2 years Annual accumulated costs In USA: US$500 In USA: US$170 including power, maintenance, In India: US$500 In India: US$37 depreciation Source: Authors. Some options expanding and realizing the benefits of EAC are noted below: Low energy use/solar. Small EAC units using solar photovoltaics (PV) are available in several com- mercial and prototype models. Manufacture and dissemination could be done through commer- cial channels providing cost-efficient cooling in grid-and non-grid settings. I Transfer of technology. EAC technologies are a fertile field for South-South transfer of technology, in particular with regard to small residential coolers and some agricultural applications. .Support possibilities. EAC has substantial applicability as a demand-side management tool, in gov- ernment offices and schools. Technical assistance to developing countries, pilot programs, and demonstrations all may provide further opportunities for EAC. Introduction 7 Figure 1.3. Direct Evaporative Air-Conditionerfor Transport Use Note he EAC unit(onthe forklift at right) wasbut by imatran andisbeinginstalledontoatytransitbusinDenverColorado. More than 400 buses in the United States and more than 1,200 in Australia use evaporative air-conditioning. Source: R. Foster. . 33 .3/ 17.2 19.6 15.0 Tehran, Iran 38 .3/ 16.7 19.9 13. 7 Africa Cairo, Egypt 38 .9/ 23. 3la 25.6 22.1 Casablanca, Morocco 34 .4/21.1la 23. 1 19.0 Europe Madrid, Spain 35 .6/20.0 22 .3 18.2 South/Central America Cali,. Afghanistan 36 .7/17.8' 20.6 15.6 Singapore, Singapore 32 .2/26.1 27.0 25.6 Middle East Riyadh, Saudi Arabia 43. 9/20.0 23. 6 17.1 Ankara, Turkey 36 .1/18 .3 21.0 16.1 Jerusalem, Israel 33 .3/ 17.2. Springs, Australia 39 .4/20.0 22.9 17.6 Beijing, China 35 .0/ 23. 31 25.1 22.1 Bangalore, India 35 .5/ 23. 3 25.2 22.2 Christchurch, New Zealand 27.8/17.8 19 .3 16.4 Melbourne, Australia 34 .4/20.6 22.6 18.9 Kabul,