Dec 01, 2004
Safe water from SODIS and SPOWTS
You will find detailed practical help with the SODIS process at its official site. It is also worth browsing the links to gain an idea of SODIS’s potential.
Solar Powered Ozone Water Treatment Systems [SPOWTS] is technologicaly a couple of notches higher than SODIS, but still quite friendly to use. It was introduced in Nepal by those concerned by the litter of empty water bottles that trekkers leave behind. Also, as trekkers found branded, bottled water more pricey as they moved away from market towns there was an economic opportunity that could lead to micro businesses.
A SPOWTS installation consists of a solar photovoltaic panel driving a 1gm/hour ozone generator. Water to be treated is circulated by a small electric pump and made to interact with controlled dosages of ozone.
Sagarmatha Pollution Control Committee has estimated that 11,508 litres of kerosene and 125,272 kg of firewood were used by organized Everest expeditions in 1996, equating to 256 tonnes of CO2 to make polluted water safe for drinking. SPOWTS is targeted to be a solution to this problem. It was developed in New Zealand by Empower Consultants and manufactured by Lotus Energy in Nepal and implemented by Himalayan Light Foundation. The whole exercise has been co-ordinated by Annapurna Conservation Area Program. So far 16 SPOWTS installations have come up in remote areas. Trekkers quite happily patronise these micro businesses. Empty water bottles are recycled and money stays in the village.
SODIS and SPOWTS are worth the consideration of organisations involved in development initiatives.