Off Grid Solar Systems:
An off grid solar electric system is perfect for those who desire true energy independence and are willing to live in ‘energy efficient’ and mindful way. Island Solar specialize in off grid solar electric systems in the Bahamas.
It is important to understand a few key points if you would like to live completely off grid. When we design an off grid system, we need to size your system for the lowest sun months of the year. Off grid systems require batteries and this makes this type of system the most expensive alternative. Learning to live in an off grid home is very satisfying for the majority of our customers. Remember, change is not sacrifice! Many, many people live comfortable and normal lives in off grid homes.
Off Grid solar systems has the dual purpose of reducing electrical bills and providing electricity during blackouts and it can be installed in stages. Your building is normally designed to accept only one source of electricity (from the country’s electrical grid). So the first step would be to retrofit the building to accept another source (ie. solar). Island Solar installs a system called a “Grid Back Up/ Pre Solar System) which is simply a solar system without the solar panels (you can easily upgrade by adding solar panels later). This system will operate just as a UPS/generator would, so in the event of a blackout, electricity will be drawn out of the batteries by way of the inverter. This process is seamless and most time not noticeable. The run time of this system is determined by the battery bank capacity size. This system will be programmed to recharge batteries from the utility grid once it is restored. There may be a slight increase in your electrical bill due to the battery charging but a small price to pay than to suffer during those annoying power outages (blackouts). This system provides clean quiet electricity (unlike noisy generators that emits harmful carbon monoxide and requires fuel and maintenance). We call this a pre solar package because this system can be easily upgraded to a complete energy production solar system simply, by adding solar panels to harvest the sun’s energy to recharge the batteries instead of recharging from BPL grid.
“How much Solar do I Need and how much would it cost?”
As of July 1, 2018, here in the Bahamas, the average cost of a professionally installed, code compliant off grid batterybased solar system (using maintenance free lithium batteries)is about $6.97 to $7.10 per watt. The average cost of the same size grid tie battery-less version in is about $5.95 to $6.05 per watt installed. The average home consumes about 600 Kwh of electricity monthly, which would require a 5000 watt off grid battery based solar system, which equates to about $35,500.00 (5000 x 7.10) BSD. The same size system grid tied without batteries would equate to $30,250.00 (5000 x 6.05) BSD.
A simple formula to get an idea of how much solar you need; take the average monthly Kwh consumption, multiply by 1000, divide by 30 (days), divide by 5 (sun hours) then divide by 0.65 (systems efficiency). You would then multiply this number by the cost per Kwh for the type solar system you want to install to get an idea of the cost. An Island Solar professional would still have to conduct a site visit to produce a more accurate estimate for your building.
Bahamians let no one sell you a dream when you go shopping for solar! Have a professional physically assess your solar needs first then get it done right the first time or pay for costly corrections later!