There is a growing awareness across the country about environmental impact and the effects of global warming. Many organizations are looking for ways to serve as models of energy conservation. However, finding the right green technology to cut emissions and help ease economic strains can be extremely difficult, especially when it comes to renewable energy.

Perkins Local Schools, Perkins High School and Brian Middle School, in Sandusky, Ohio, used a Renewable Energy Scorecard to analyze several renewable energy options based on the most significant environmental and economic drivers.  >> Photos courtesy of Perkins Local Schools.

Take solar power generation, for example. Given their visibility and well-established track record, photovoltaic panels are typically the first — and often only — renewable technology on people’s radar. But solar is not always the optimal choice economically: most states offer no tax incentives or rebates to help decrease startup costs; regional electric rates may be too low for solar to be competitive; and a lack of sunshine in a particular location may not make the investment worthwhile.

In reality, most organizations that express a desire for solar aren’t tied to a particular technology. They just want some sort of renewable component to their energy management strategy. Locating the technology with the most significant economic drivers requires an analysis of location-specific variables, including:

• Fuel availability
• Energy prices
• Heating and cooling degree days
• Financial incentives and offsets
• Financing structure

Compiling the information required to make a sound financial decision is labor intensive, and for most organizations requires expertise that falls outside of their core competencies. But the task is not impossible and need not be daunting, as evidenced by Perkins Local Schools in Sandusky, Ohio.

Rank and File

Like many K-12 districts, Perkins contended with an outdated and inefficient infrastructure. The district’s boiler plant dated back to the 1920s, for instance, and needed an overhaul. Numerous building envelope repairs were required to prevent air loss.

Along with the infrastructure improvements, the district wanted to reduce its dependence on traditional energy sources and lock in a portion of its spending. So, Perkins turned to energy services provider Honeywell to better understand the renewable landscape.

The company helped the district analyze several options using its Renewable Energy Scorecard, a first-of-its-kind selection tool that helps pinpoint the technology with the most significant environmental and economic drivers. The tool looks at six proven renewable technologies, such as solar, wind, biomass and geothermal, and provides a simple payback for each, giving organizations a financial forecast derived from calculating tax implications, rebates, subsidies and other incentives.

Starting with fuel availability, the scorecard for Perkins showed an abundance of biomass in the surrounding area — more than 141 tons of wood waste per square mile. Wind also appeared favorable, with an average velocity of 5.7 meters per second, a desirable speed to economically generate electricity.

Heating degree days far outweighed cooling, with an average air temperature of 48 degrees Fahrenheit. This indicated a higher demand for natural gas for a greater portion of the year, biasing the analysis toward biomass.

In addition, Honeywell identified available state incentives that would help ease the burden in financing the project.

Once all these factors were combined and weighed against conventional energy rates, the scorecard ranked biomass thermal with the quickest payback (around six years), followed by wind (around 11 years), and solar thermal and geothermal (just fewer than 20 years each).

However, finances weren’t the only driver for the district.

Blowing in the Wind

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The analysis showed biomass-generated heat would provide the greatest savings. However, a biomass solution would take longer to implement and require the district to negotiate a long-term contract for fuel. Furthermore, school officials wanted their first renewable project to be as simple and visible as possible. As a result, the district turned its focus to wind, which would allow it to take advantage of a micro-climate caused by the winds blowing in from Lake Erie and eliminate any fuel-sourcing issues.

Administrators decided to install three 20-kW wind turbines at the high school and middle school complex, with an anticipated output of 144,000 kWh per year. Based on these figures, the turbines — slated for installation in fall 2008 — would cover more than 11 percent of the electrical load at the complex and reduce annual CO2 emissions by more than 130 tons.

The district combined the turbines with the other conservation measures, creating a $2.1-million program. The improvements were funded through a performance contract with Honeywell that guarantees energy savings of approximately $136,000 per year during the next 15 years. So, the work won’t impact capital budgets or require additional taxpayer dollars.

The project is also expected to generate operational and maintenance savings of around $56,000 per year without a loss of maintenance personnel. And, thanks to a state grant of $150,000, the overall cost of the turbines was cut in half.