Evaluating Your
Green Options

As renewable energy industry professionals with decades of experience, we are sometimes shocked at what we hear and read about in the industry. Just recently, we read in the local newspaper that a 4-collector solar heating system provided up to 80% of the heating needs and 100% of the hot water needs for a 3,500 square foot house. With wildly optimistic claims, it’s remarkable that renewable energy has not already replaced fossil fuels altogether.

Our customers are frequently considering a variety of renewable energy technologies. They are typically motivated by a combination of wanting to save energy costs, wanting to preserve the environment, and wanting to insulate themselves from what may be a long-awaited economic reckoning that undermines our societal infrastructure. Everyone has their own reasons, and we’re all for the adoption of renewable energy systems. There is a lot of information about “green technology” out there, and it doesn’t always make for easy comparisons. We thought the Sustainable Guide would be a good place to talk about how you might compare your options to make sure your objectives are achieved.

Most clients have a primary objective of saving energy dollars, and a secondary objective of being “green.” We encourage them to compare technologies based on two economic parameters: Initial Cost and Operating Cost.

Initial Cost is the cost of the renewable energy component of the system. As many systems are offered as a combination of renewable and non-renewable components, it can be important to understand what part of the system will “pay for itself” and what part is simply needed for backup or represents infrastructure such as the heat distribution equipment. Tax credits, rebates, and other incentives typically impact the Initial Cost.

Operating Cost is the monthly or yearly cost of the system performing its task. This includes incremental maintenance and energy costs. A solar heating system that provides half of a home’s heating energy will have about half the operating cost of a non-solar heating system.

As a simple example, if we compare a solar-electric system to utilizing the existing power grid: the initial system cost of using the power grid looks lower, and the operating cost of using the existing grid looks higher. Over time, it is likely that grid-provided electricity costs will increase while the solar-electric system is likely to provide electricity consistently for 30 years or more with very little maintenance.

A more robust analysis of this example would look at the initial cost of coal-fired power plant construction, clean-up costs resulting from coal combustion, which emits not only huge amounts of greenhouse gases, but also mercury, uranium, and other heavy metals, and other less obvious operating costs. The former GM at Dankoff Solar Products, Paul Benson, when asked why solar electricity was so expensive, was fond of responding, “What makes you think coal-fired electricity is cheap?”