by Andrew Jorgensen
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Solar panels installed atop the roof of the turf care facility at
Candler Hills Golf Club in Ocala, Fla., meet all electrical needs
for maintenance activities. |
For obvious reasons, renewable energy continues to warrant significant attention and demand in nearly every industry today. Fortunately, as technology continues to improve and greater efficiency in real-world scenarios are achieved, solar systems are becoming more practical than ever before. In this case study, the method of capturing solar energy for conversion into usable electricity is being utilized with great success at Candler Hills Golf Club in Ocala, Fla.
In 2011, a solar system comprised of 297 photovoltaic panels was constructed atop the maintenance facility at Candler Hills Golf Club. Photovoltaics are a method of generating electrical power by capturing solar radiation and converting it into usable energy. For our system, inverters are used to convert direct current (DC) solar energy captured from panels on the roof into alternating current (AC) electricity that can be used to power building utilities and equipment and charge batteries.
The 297 solar panels combine to produce roughly 56,000 DC watts of energy and, for our location in central Florida, approximately 90,000 kilowatt hours (kWh) per year. This is more than enough to meet all of the electrical needs at our facility. Any unused power can be sold back to the energy company because our system is tied back to the power grid through a two-way meter. The system is not connected to a bank of batteries because a storage system is very expensive and not practical for our needs. So if the power goes out, we lose power as well.
Energy production varies with location and time of year. For our locale in central Florida, the peak season for solar energy production is September through April because the sun is nearly perfectly perpendicular to the rooftop panels, resulting in maximum absorption.
Conventional wisdom would suggest that energy production would be highest during the warmer months of May through August, when sun intensity and duration are greatest. The contrary is actually true for two reasons.
First, the angle of the sun is directly overhead, resulting in much of the solar radiation glancing off the panels. Second, extreme heat causes solar panels to be less efficient, which must be accounted for during the summer in southern climates like Florida.
The panels we chose have an 80% energy efficiency rating at 30 years, meaning that in 30 years they will still be producing nearly 45,000 DC watts, or 80% of their original 56,000 DC-watt capacity. The system was designed to produce 115% of our maintenance facility’s current needs, knowing that we will eventually be consuming 100% of what the panels produce as the output efficiency of the panels reduces over time and our energy use increases.
We had considered the solar panel system for some time, but the initial cost was significant, which originally caused us to opt against the project. In early 2011, however, our energy provider announced a photovoltaic rebate program that offered a refund for a portion of the cost of the system. Since it is a rebate, funding had to be provided up front to the system installer, with the rebate check from the energy supplier coming later.
The rebate was dependent on passing a review of the proposed system and building in which the system was going to be installed. Helping us capture the most solar energy is that our building faces due south and has the perfect roof pitch for solar panels. Also, the building is still quite new and the shingles should last another 15 years or more, which reduces ongoing maintenance costs associated with removing the panels for reshingling after system installation. In our case, once our energy provider inspected the system and building, we passed with flying colors and were approved for a rebate of nearly $90,000 toward the cost of the system.
This reduced the cost per watt of the system down to approximately four dollars. Today, we are also able to use the system for a 30% tax credit on our company taxes at the end of the year, further offsetting the cost of the system. So, when considering the rebate combined with the tax credit, the total cost of the system ended up being just 40% of the original estimate.
Furthermore, we recently had an energy audit performed by the energy supplier. The audit resulted in installing several additional energy-saving mechanisms, including photocells on outdoor lights, timers on motors and pumps, energy-efficient fluorescent lighting, and energy-efficient air conditioning in the offices.
Looking forward, our system has a payback of roughly 12 years. This means that in 12 years, when everyone else is still being billed for power, we will no longer have to pass on these charges to our golf customers.
Clearly, it is a way for us to reduce expenses without any adverse effects to course quality. Over the 30-year life of the system, and excluding installation costs, we are looking at a total savings of roughly $200,000 in electrical costs.
