It is easy to get an instant answer to the question “what’s the single major reason for high electricity bills in homes.” It is electric geysers. Yes we know, yet we have no single solution acceptable to all to get our daily supply of hot water. The last decade has produced a few viable alternatives, but they have not yet replaced the age-old geyser.
The challenge of hot water lies in the very nature of its need and this challenge can only be met with by using cold water! Unfortunately such a suggestion would get laughed at as impractical, for hot water bath has been part of our civilisation, biologically or culturally.
Though we need hot water mostly during the morning hours, it could also be needed at any time depending on the family lifestyle and guest arrival, with varying water quantity each time. Therefore, electric geyser comes to stay as an anytime, any quantity solution. On a quick look, energy consumed in heating the water may not appear like a major problem at all, compared to say some industry; but thousands of homes each with 2 or 3 heaters may surpass many industries in energy consumption. The problem is getting critical even in rural areas, with firewood getting depleted at rapid rate.
Solar water heaters have emerged as an effective alternative to the electric geyser, with 300 sunny days in a year in most areas of India. Roof-top installations, panel facing south, could be seen everywhere today, both on flat roofs and of late, sloping roofs too. The water storage tank comes with a built-in electricity geyser, an option which is not very desirable. In case of water not being hot enough, we end up heating all of 100 or 200 litres of cold water, consuming much more energy.
If really hot water is expected, we can route the solar water through a conventional electric geyser, thus reducing the power needed to heat up already warmed-up water.
Keep it simple There have been complaints about lower water pressure if water is so routed, which can be resolved by the plumber. However, bringing solar water directly to the bathroom saves on extra connections, besides the confusing method of providing both fresh and solar water inlets for the geyser. One back-up electric geyser can be provided in the upper floor, with gravity flow to the ground floor baths.
Providing long piping for solar hot water is not advisable, considering the amount of cold water that flows first, before we get warm water. For this reason, avoid it in kitchens and wash basins. A larger family can save by staggering the bath timings, instead of installing higher capacity units. Also, locating it to get best sunlight hours is very important and so is occasional cleaning of the panel surface.
Most plumbers today know how to get the best from solar water heater connections, so it is time to look for other lesser known options.
(The writer is an architect working for eco-friendly designs and can be contacted at varanashi@gmail.com)
