OFF-GRID LIVING

OFF-GRID LIVING USING RENEWABLE AND ALTERNATIVE ENERGY SOURCES

Living without grid supplied electricity does not mean you have to rough it. There are alternative energy sources that can make your living almost as comfortable with the added advantage that you will be using renewable and sustainable energy sources like electricity generated from the sun, wind or water energy.

Energy efficiency plays an important role in keeping the cost of an alternative electricity system down. The general rule is that when electrical equipment or appliances generate lots of heat like geysers, stoves, heaters, tumble dryers etc they normally have high consumption figures. The use of energy efficient appliances and lighting as well as non-electric alternatives wherever possible can make alternative electricity an environmental friendly alternative to gasoline generators or utility power.

Lighting: Solar generated electricity. Compact fluorescent energy saver lamps use only 20% of the energy a normal incandescent bulb consumes. The latest technology uses LED lights that uses even less electricity than compact fluorescent lamps. Please take note that low voltage halogen downlighters are low voltage but NOT low energy!

Cooking: Gas stove and cooker, wood, solar cooker. Microwave oven: Small microwave ovens can be used successfully from solar systems especially because their operation times are normally short.

Hot water: Solar water heating, LP gas geyser, boiler.

Small appliances: Many small appliances such as toasters and hair dryers consume a very large amount of power when they are used but by their nature require very short or infrequent use periods, so if the system inverter and batteries are large enough, they may be used on solar generated electricity.

Refrigeration: If an electric refrigerator will be used, it should be a high efficiency (super low consumption type. An energy efficient refrigerator/freezer uses approximately four times less electricity than conventional refrigerators. The higher cost of good quality energy efficient refrigerators and freezers is justified by savings in the number of solar modules and batteries required. Gas powered absorption refrigerators are a good choice in applications where they are not used permanently, like in weekend or holiday cottages. In homes where these appliances are used permanently, the electric option will be cheaper and more convenient. Washing: Most washing machines on a cold cycle have a fairly low consumption figure and can be run off an alternative electricity system.

Ironing: Electric irons consume about 1,500 watts/hour and it is expensive to operate them from solar electric systems. A silent type power generator is a good option.

Tumble drying: Tumble dryers are heavy consumers of electricity and again a silent type power generator will be a good option. LPG gas clothes dryers are also an option.

Heating: Gas and wood are better alternatives for space heating. Good passive solar design and proper insulation can reduce the need for heat.

Entertainment: TV, video, radio and hifi’s are low in consumption and can be easily run off an alternative electricity system. Although computers consume more power, they are relatively low in consumption. Notebook computers use less power than table top models.

Water supply: Submersible and pressure pumping systems can now run off solar power and water can be pumped and pressurised to high heads.

A typical alternative electricity system would consist of the following components: The system can make use of one or more charging sources. When more than one charging source is used, it is called a hybrid system. A wind/solar hybrid system is a good approach in coastal areas. A silent type generator could be necessary to backup the solar electric system during times of continuing inclement weather or for running heavy loads.

Energy harvesting equipment Solar panels, wind turbines or hydro turbines can harvest green energy from nature. This energy is both environment friendly and sustainable.

Petrol or diesel generators can be used for backup or to provide for peak loads, but this is not an environmental friendly approach and their use should be minimised. The solar panels and or wind turbine should be sized to match the average daily power consumption in watt hour.

Power storage. Battery bank. This should be sized to give you a few days backup storage capacity (autonomy) for times when the wind does not blow or the sun does not shine. Power conversion In order to change the stored battery power into usable 230 Volt alternating current an inverter is used. This inverter should be sized to be able to cope with peak load and demand.

Designing an alternative electricity system.

The size of an alternative electric system depends on the amount of power that is required (watts), the amount of time it is used (hours) and the amount of energy available from the sun, water or wind in a particular area (sun hours per day).

These factors will determine the eventual cost of any alternative electricity system. A system design and costing can be made according to your exact needs. In order to do this, information on the equipment you intend to use is needed.

Estimated consumption in watt hour per day basically calculated as the sum (in watt hour) of all the appliances used: Example

10 X energy saver lamps 12 watt @ 5 hours per day 600 watt hour

1 x TV 120 watt @ 3 hours per day 360 watt hour

Total estimated daily consumption 960 watt hour

Peak load calculated as maximum power drawn with all the above equipment on = 240 watt

Click here for more info ...
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Copyright 2007 OMNISOLAR | info@omnisolar.co.za