Is there a problem with storage? Can you store solar energy?
Electrical energy is expensive to store, and storage is generally not included in CSE’s solar projects. However, a key benefit of solar, especially here in the Southeast, is that solar projects generate the most electricity on sunny days, which are generally the time that electrical demand peaks (because of air conditioning use.) Therefore, installing more solar in North Carolina puts extra electricity onto the electric grid at the time it is needed most.
What makes solar work here in North Carolina?
On August 20, 2007, North Carolina became the 25th state – and the first and only in the Southeast – to enact a mandatory renewable energy and energy efficiency portfolio standard (REPS) into law. The REPS requires that 12.5% of the electricity sold at retail by all North Carolina electric utilities be generated by renewable energy resources or replaced by energy efficiency by year 2021.
Solar energy is a key part of the REPS which includes a “set aside” for either solar thermal or solar electric generation. The percentages and milestones for solar are: 0.02% of sales by 1/1/2010, 0.07% of sales by 1/1/2012, 0.14% of sales by 1/1/2015 and finally 0.20% of sales by 1/1/2018. North Carolina is on track to exceed these targets earlier the dates required by law.
In addition from 2007-2015 North Carolina solar projects could benefit from North Carolina Tax Incentives. These incentives helped to stimulate the industry and create economies of scale to bring down cost. We have reduced consumption costs significantly since 2007 and are now able to build utility scale solar projects without state tax incentives.
North Carolina solar projects also benefit from Federal tax incentives which were recently renewed until 2020.
Why are most solar projects in North Carolina installed on the ground rather than rooftops?
Rooftop solar is popular in states that are “deregulated” (where consumers have a choice of their electric provider). In these states, solar companies can offer to install a solar generator at a home or company and sell the building owner electricity at a fixed, long term price, without requiring an upfront capital investment from the building owner. This is known as “third party sales” since the solar company (rather than the utility) is selling electricity directly to the building owner.
The situation is different in regulated states such as North Carolina. In NC our electric utilities are granted a monopoly to sell electricity, and solar companies cannot sell electricity directly to building owners. Because of this, a building owner must own the solar equipment (and make a high upfront capital investment) in order to benefit directly from using the solar electricity. Many building owners are not able to make this upfront investment, although there are examples of successful rooftop solar projects in NC where this has been possible due to the building owner’s commitment to solar. Alternatively, a building owner can rent their rooftop to a solar company (or other group), who will sell the electricity to the utility at wholesale prices. This model has not generally proved to be enough incentive to generate a strong rooftop solar market in NC.
How long does it take a solar panel to return the energy that was used to create it?
The energy payback period for solar photovoltaic panels is now between 2-3 years. You can download a calculation done by the US department of energy here. Note: Carolina Solar Energy uses crystalline silicon modules.
If you install solar panels on the ground, can the land be used for anything else?
Yes. On many of Carolina Solar Energy’s solar farms, we contract with local farmers who pasture sheep during the spring, summer and fall when the grass is growing. The sheep control the grass, so that it does not grow up and shade the solar panels. We attach a gutter to the bottom of some of the rows of the solar panels, and collect rainwater for the sheep to drink. We do not use goats or cows because they might eat the electric wires or jump up on or rub against the solar panels.
What happens at the end of the solar farm life?
The solar panels are manufactured and warranted to generate electric power for at least 20-25 years, and we anticipate that the solar farms installed now may remain in the field generating power for 30 years or more. At the end of the useful life of the solar panels, the entire system can be removed and recycled. The component metals of the solar system, steel, aluminum and copper can be recycled, and their value is higher than the cost of removing the system. Carolina Solar Energy installs panels on driven metal pilings rather than concrete, so that at the end of the solar farm’s useful life, the solar panels and pilings can be removed with little trouble and the land left clean and looking like before the solar farm was installed.
What type of solar technology does CSE use?
CSE uses modules made of crystalline silicon. The crystals are “grown” from a solution made of pure molten sand. One of the world’s purest silicone mines is in western North Carolina near Asheville.