Green Heating and Cooling
One thing that’s really important to us is being the right temperature. Heating and cooling our homes, workplaces and cars add up to major household expenses and, as importantly, are huge energy guzzlers. Anyone aspiring to eco-friendly living or green building is likely to be interested in green heating and air-conditioning.
Alternative, sustainable energy sources are the way forward, and millions are already using them to heat and cool the home. Solar panels to generate electricity are a common sight, but another kind of solar energy is less familiar to most people. Passive solar energy (or ‘direct gain’) doesn’t convert sunlight into power, but depends on heat transfer and smart building design. On one level it’s as simple as site-specific design and materials: room arrangements, where windows and doors are placed, roof design and insulation. Great design optimizes the building so it’s cool in summer and warm in winter. It also utilizes thermal mass, which is about buildings absorbing and releasing heat relative to the daily temperature fluctuations.
Wind farms are another common sight now around the world, but home wind energy generation is also a reality. Students in Oregon have devised a minute domestic wind-powered water heater that could potentially be used to heat a home – as long as the wind is blowing. Another new invention is the ice-powered air conditioner. It makes ice during the night which is then used for cooling the unit in the daytime, saving on energy and costs.
Geothermal energy is being explored both for greener electricity generation and for both green heating and cooling. We all know the earth has a seething core. Digging down just a few meters (typically less than 10 meters) can allow tapping into geothermal heat. It’s not a direct process. A heat pump taps into subterranean geothermal wells to transfer heat via a carrier fluid. That heat can then be used for either heating or cooling.
It’s not just new techniques and technologies that are providing green heating and air-conditioning today. Seemingly small tweaks of existing technologies and systems can be just as helpful for people wanting green homes, and systems that were developed for large buildings are being adapted for domestic purposes.. The DEVap (desiccant-enhancedevaporative air conditioner) is an innovation that is said to be 40-90% more efficient than traditional aircon systems. Work has also been done on substituting ammonia or carbon dioxide for the greenhouse gasses called fluorocarbons on which traditional air conditioning has depended.
Aircon in cars is a notorious source of high energy use and fuel consumption. Since many cars sit in the sun all day it’s amazing that more use has not been made of solar air-conditioning. One exception is the Toyota Prius. Solar panels in the sun roof power a fan. While the car is in the sun it is cooling itself, reducing the need for using the aircon when the driver returns. It’s innovations like these that can transform our energy usage and satisfy our need for temperature control for optimum comfort.