- RETScreen is a software tool for evaluating the feasibility of renewable energy and energy-efficiency technologies.
- The tool estimates energy savings, costs, and emissions reductions for clean energy projects.
- The Energy Efficiency Model compares a clean energy project with conventional technology.
Evaluating the feasibility of renewable energy and energy-efficiency projects can be time consuming and expensive. RETScreen is a software analysis tool that offers a low-cost method for evaluating the energy savings, emissions reductions, financial viability, and risks for various renewable energy and energy-efficiency technologies (RETs).
The latest version—RETScreen 4—includes renewable energy, cogeneration and district energy, plus a full array of financially viable clean power, heating and cooling technologies, and energy-efficiency measures. This useful resource can help decision makers quickly and inexpensively determine the technical and financial viability of potential renewable energy, energy-efficiency and cogeneration projects. RETScreen has been used by more than 315,000 people in 222 countries, and has helped users save an estimated $7 billion in energy costs worldwide.
Clean Energy Project Analysis
The Clean Energy Project Analysis tool can be used to evaluate the energy production, life-cycle costs, and greenhouse gas emission reductions for various types of proposed energy-efficient and renewable energy technologies. RETScreen handles these projects and more. After establishing initial settings and site conditions, the software uses a five-step process to determine project feasibility:
- Energy Modeling—energy benefits compared to a conventional alternative
- Cost Analysis—incremental costs of clean energy projects
- Emissions Analysis—greenhouse gas emissions reduction using a standardized methodology
- Financial Analysis—considers cash flow, taxation, incentives, and environmental credits
- Sensitivity and Risk Analysis—Monte Carlo simulation on input variation
To do this, RETScreen incorporates several important databases on the climate and clean energy products (over 7,000 devices), along with a help manual, and engineering tools. During the analysis, RETScreen offers three levels of data refinement that it calls Methods. These range from minimal choices to more complex, with custom data inputs, such as wind turbine power curves, regional emissions data, and item-by-item cost analysis.
The Energy Efficiency Model used a five-step process to compare a proposed clean energy project to a base case scenario involving conventional technology:
- Fuels and Schedules—identify fuels used and fuel prices. Include building operating schedules for each day of the week.
- Facilities Characteristics—include building systems and equipment, as well as the estimated cost for each measure.
- Summary Section—estimates energy use and cost of the base case and proposed case, compares RETScreen estimates against past energy use, and provides a benchmark against similar facilities.
- Emissions Analysis—estimates the potential emissions reduction from the project.
- Financial Analysis—enter financial parameters to evaluate the financial viability of the project.
Energy-efficiency improvements in a 40-unit apartment building, demonstrate how RETScreen works:
- Installation of low-flow showerheads resulted in a 35% reduction in water use and $3,000 in savings
- Reducing the water temperature from 140°F to 130°F (60°C to 55°C)
- Implementing heat recovery at a cost of $15,000 resulted in a 15% efficiency gain
- Installing a new water at a cost of $40,000 resulted in a 20% improvement in energy efficiency
In RETScreen, you would first select your geographic location to determine your climate zone and set your hot water use by implementing RETScreen defaults or customizing with your own. In this example, RETScreen calculates a 53% reduction in energy consumption just by reducing flow and water temperature and adding heat recovery with a simple payback period of 0.9 years. With these improvements, switching fuels and upgrading the boiler results in roughly 20% efficiency improvement with a simple payback period of 5.4 years. The overall payback period is 2.2 years. If only the heating system changed, the payback period would be 2.5 years. This illustrates how RETScreen can provide varying feasibility estimates based on multiple inputs and scenarios.
Find Out More
RETScreen 4 is a Excel-based program for project analysis. RETScreen Plus is an online energy-management program that allows users to track the ongoing performance of projects and facilities. While RETScreen is a do-it-yourself program, training materials and instruction are available. See the RETScreen website for more information.