Solar Energy Systems

There are a wide range of solar energy systems currently available. The systems most commonly used in Bermuda are:

• solar water heating where solar thermal collectors absorb the sun’s radiant heat energy to directly heat hot water for residential or commercial buildings;
• photovoltaic (PV) systems, which use sunlight to drive the production of electricity;
• solar direct pool pumps, which make use of PV technology to run a pool circulation pump.

Solar Hot Water Systems

Solar water heating has seen much advancement since it inception in the late 1800s. Today’s solar hot water systems are extremely efficient and cost effective. On average, up to 30% of a home’s energy consumption is used to heat water for regular household use. A solar hot water heater uses the suns radiant heat energy to heat the water thus reduces this cost by 80% or more. This large monthly savings helps to provide a quick return on investment. Solar water heating is a great environmental and money saving option for homes and businesses providing maintenance free hot water all year round.

Solar water heaters generate hot water for your home utilising a well-insulated storage tank and roof mounted solar collectors. A solar storage tank will typically have an additional outlet and inlet connected to and from the collector.

Solar water heating systems also also fully redundant, that is they come with a backup heating source to ensure the water is always kept at hot even under extended periods of cloudy days.

How Solar Hot Water systems work

• The sun’s radiant heat energy is used to heat a roof mounted solar collector. The water is heated as it passes through that solar collector before returning into your home’s hot water tank.
• When there is sufficient heat to be drawn from the solar collectors, a controller automatically activates a pump, which will pull cold water from the storage tank sending it through the collectors to be heated. The heated water continues it’s circulation loop back to the storage tank for consumption. This process continues as long as there is useful heat to be drawn from the collectors.
• During extended times when there is little or no sun, a backup heating system, an electric element in the storage tank, will automatically keep the water at preset temperature. In Bermuda many of our customers unplug their water heater for up 8-10 months of the year, only requiring some supplemental heating in the winter months.
• A solar hot water system is typically the first and most cost effective step. With a solar hot water system the sun’s heat is used to directly heat the water so there is no electricity generated and no loss of energy. They are so effective that it would take a very large PV system, at double or triple the cost to producing enough power to offset the same amount of water that a solar hot water system can offset. A solar hot water system along with a PV system will provide the best economics and space-efficiency on your roof.

Photovoltaic systems

Photovoltaic (PV) solar systems can be used in a wide range of products, from small consumer items like calculators to large commercial solar electric systems.

Photovoltaic is derived from the Greek words photo, for light, and volt, for electricity. Individual PV cells are electricity-producing devices made of semiconductor material such as silicon, polycrystalline thin films and single-crystalline thin film. Individual PV cells come in many sizes and shapes, from smaller than a postage stamp to several inches across, but typically produce about 1 or 2 watts of power. To boost the power output of PV cells, they are often connected together to form PV modules that may be up to several feet long and a few feet wide. Modules, in turn, can be combined and connected to form PV arrays of different sizes and power output, to meet almost any electric power need.

Modules or arrays require structures to point them toward the sun and components that take the direct-current electricity produced by modules and “condition” that electricity, usually by converting it to alternate-current electricity. Thus, a PV system may also include electrical connections, mounting hardware, power-conditioning equipment and batteries that store solar energy for later use. All these components are referred to as the “balance of system” (BOS) components. All these components are included in your systems cost.

How PV works

• Solar panels use light from the sun to power a series of reactions that generate direct current (DC) electricity. The amount of electricity a system can produce is based on severable  such as, the number of panels being used, orientation, sun hours and shading.
• An inverter converts the DC electricity from the panels into to alternating current (AC) electricity. AC electricity is used to power homes and is the same electricity received from power companies.
• Once converted, the AC electricity is routed into the home and immediately available for use. The solar system will produce clean electricity to be used throughout the home. Since there are no moving parts there are no maintenance concerns.
• While the PV system is producing power, that power will either be used to directly offset electrical loads in the home. In the event that a PV system is producing more power than a home needs, that excess power can be sold back to BELCO, further lowering your energy bill and offsetting future energy usage.