Living in an Off-Grid Home

Solar Power Systems for Homes not connected to an Electricity supply.

Living in an Off Grid home is more popular than ever.  Off grid homes are totally sustainable, environmentally friendly and are just like homes that are connected permanently to the electricity grid. There have been huge advances in off grid power technology and today, a whole range of generatiing configurations are now possible using a mixture of sources that cater for the individual, family or community.  Configurations may include a mixture of electrical generating sources.

Generating sources include:

·         solar panels

·         wind genertors

·         small hydro-electric generators

·         diesel or petrol generators

·         hybrid systems comprising of two or more of the sources mentioned above

Off grid systems also known as Remote Area Power Supply Systems (RAPS) or Stand Alone Power Systems.

Typical uses of small to medium off grid power systems are rural homes and cabins, holiday homes, and small community power supplies. We receive lots of requests to design off-grid power system, but it is worth stating that you must do your sums correctly.

STEP ONE

Make sure that you know what power you need.  It sounds obvious, but there is a huge difference between watt hours and kilo-watt hours.  Thus, if you want to run your house off-grid and you need "2000 kW Hrs" of electrical energy then you may not have read your electricity bill correctly!!  Just to be clear.  2000 kW Hrs stands for 2000 kW Hrs or 2000 x 1000 watts per hour or 2,000,000 watts.  If this was a quarterly figure then dividing by the number of days in the month you will arrive at another huge number. Let's assume that your electricity bill reading from Jan-March is 2,000,000 watt hours.  Dividing this by the number of days (91) in the quarter then we end up with 21,978.02 watts per day?  What the hell does that mean exactly? It means nothing unless it is attached to the duration (TIME) of use. 2,000,000 Watt Hours is the amount of electricity you used in a three month period.  The term watt-hours is used to assign a cost value to each watt used.  You pay for consumption. That is, for each watt of electricity consumed, you pay a price assigned by the electricity company.  You have to bear in mind, that if a bulb is rated at 65 watts, for example, it will use 65 watts of electricity for every single moment it is switched on.  Hence the reason why electricity is charged according to time and why you receive your bills stating WATT HOURS or KILO WATT HOURS.

STEP 2

If your electricity bill is really 2,000kWh per quarter then you need to switch off all your appliances and examine every single appliance to find its rating in WATTS. At the same time think about the amount of time (HOURS) you use the appliance. This is better known as a LOAD CALCULATION

The process of working out your electricity consumption is the basis of your calculations to size a solar or wind powered system. What we're after is the total watt hours per day or per week.  As you can see 2,000,000 Watt hours is a lot of energy and to meet that demand you will need a lot of solar panels, approx 100 or more.  Can you imagine that and think of the cost!  Scary!

STEP 3

Get in touch with us and we'll help you design a system that meets your exact needs.

If you need an "off the shelf" system then consider the following. Call us for pricing.

CUSTOM MADE SOLAR POWER SYSTEMS FOR OFF GRID HOMES

 

+++We offer a customised design service and are able to design a system that meets your exact needs. Everything we do is ecological responsible and sustainable.  We offer complete, efficient, cost effective, and environmental systems++++

 

Before we can design a system for your own off-grid home there are six essential steps to be taken. The steps are:

• 1. Estimating the Load
• 2. Sizing and Specifying the Battery Storage
• 3. Sizing and Specifying the Solar Array and/or Wind Turbine
• 4. Sizing the controller
• 5. Sizing the inverter
• 6. Specifying the System Cable

When designing any off-grid system there are a lot of factors to take into consideration, such as module shading, orientation, frame mounting options, wiring etc.Whatever process a designer takes it all boils down to a consideration of the drawbacks to designing a system. There are a lot of factors that affect any system but the main ones are:

• a) Location - the site needs to be clear, open and free of shade.
• b) Orientation - Solar arrays should be aligned to "true north" with proper inclination.
• c) Frames - mounting options are many but should maximise solar efficiency and gain.
• d) Solar Modules - these need to meet your system guidelines
• e) Solar Controllers - sized to meet the needs of the system AND the user
• f) Battery Storage - it is essential to size the batteries to the specific installation.
• g) Loads - Can they be minimised as much as possible?
• h) Wiring - What size cable is required and what effect does it have on the system performance?