Few places on earth are more in need of air conditioning and cooling than houses in Bangladesh, but the low level of income there means that the population cannot afford to buy air conditioning units. A social venture, called Eco-Cooler, has created a DIY aircon unit made of old plastic bottles and cardboard, that can fit into any window. It reduces the temperature by about 5 degrees Celsius. Given that 70% of the Bangladeshi population live in tin huts, any cooling aid that doesn’t use electricity is a boon.
In the West, we’re lucky that we have electricity, and products to buy, to make our living environment more comfortable. However, we owe it to the rest of the world to make sure that we do not add to climate change, or make life even more difficult for those living in countries such as Bangladesh. We owe it to ourselves perhaps, to exercise the same ingenuity about solving our air conditioning challenges in greener ways.
Lateral thinking – heating to cooling
The industry has perhaps started to think more laterally, for example, in the idea that hot water, conventionally used as part of a heating system, can also be used as an efficient method of air conditioning.
A hot office is typically suffering from an excess of free energy, in the form of sunlight. In conventional systems, more energy, in the form of electricity, is then used to power a mechanical compressor, to cool the office. If we look at this another way, the heat that is causing the discomfort – solar energy – can be used to heat water, that can then be used as the power source for a cooling system to alleviate the discomfort and bring the office temperature down to a comfortable level.
This type of “thermal cooler”, which can be used to supplement heating in winter, and provide cooling in summer, changes the cost-benefit equation for investment in this type of system, because it can provide savings all year round.
Increased use of Geothermal
Geothermal Heating, Ventilation and Air Conditioning (HVAC) products have actually been around for some time, but are only now coming into widespread use. Geothermal products use the earth’s heat to provide both heating and cooling systems. Piping is looped around, to pick up underground heat which is then transferred to the house. In summer, the process is reversed – heat is transferred from the house to the underground loop and then returned to the earth which is cooler at this point.
Green duct wrap
The idea of using duct wrap to reduce heat gain from air ducts isn’t new, but previous products were often irritating to the skin and emitted Volatile Organic Compounds (VOCs). A new duct wrap has been developed, made of recycled denim, picked out of landfill. Fire-resistant, this contains no fibreglass, so can be used by installers who can’t work with fibreglass.
Of course, there are those who say that ductwork is in itself energy inefficient, so a number of systems now claim to deliver air conditioning with no ductwork.
We’re gradually learning to be more innovative, and to work with what we have – something that those in less privileged circumstances have always had to do.