Energy Benchmarking

Energy benchmarking is the process of measuring and tracking a building's energy use and comparing it to similar buildings. It is an essential tool for identifying opportunities to save energy and reduce costs. In this explanation, we will discuss key terms and vocabulary related to energy benchmarking in the context of the Professional Certificate in Energy Auditing Techniques.

1. Energy Use Intensity (EUI): EUI is a measure of a building's energy use per unit of floor area. It is expressed in units of energy per square foot per year (e.g., kBtu/sf/yr or kWh/m²/yr). EUI allows for an apples-to-apples comparison of energy use between buildings of different sizes and types.

Challenge: Calculate the EUI for a building with a total energy use of 1,000,000 kWh and a gross floor area of 50,000 square feet.

Solution: EUI = (Total Energy Use / Gross Floor Area) x (365 days/year) EUI = (1,000,000 kWh / 50,000 sf) x (365 days/year) EUI = 7300 kWh/sf/yr

2. Weather Normalization: Weather normalization is the process of adjusting energy use data to account for variations in weather. This allows for a more accurate comparison of energy use between buildings in different climates or between different time periods.

3. Source Energy: Source energy is the total amount of energy required to generate and deliver energy to a building, including losses in transmission and distribution. It is expressed in units of energy (e.g., kBtu or kWh).

4. Site Energy: Site energy is the amount of energy delivered to a building's meter. It is expressed in units of energy (e.g., kBtu or kWh).

5. Energy Star Score: The Energy Star score is a 1-100 rating that compares a building's energy performance to similar buildings. A score of 50 indicates that the building performs better than 50% of similar buildings, while a score of 75 indicates that the building performs better than 75% of similar buildings.

6. ENERGY STAR Portfolio Manager: ENERGY STAR Portfolio Manager is a free online tool developed by the U.S. Environmental Protection Agency that allows users to track and analyze energy and water use, as well as greenhouse gas emissions.

7. ASHRAE Level I, II, and III Energy Audits: ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) defines three levels of energy audits:

* ASHRAE Level I: Walk-through audit, provides a general assessment of energy use and identifies low-cost/no-cost energy efficiency measures. * ASHRAE Level II: Energy survey and analysis, provides a more detailed assessment of energy use, identifies energy-saving opportunities and calculates potential cost savings. * ASHRAE Level III: Investment-grade audit, provides a detailed engineering analysis of energy use and identifies and prioritizes energy-saving measures, including costs and savings.

8. IPMVP: The International Performance Measurement and Verification Protocol (IPMVP) is a standardized protocol for measuring and verifying energy and water savings. It is widely used in energy efficiency projects.

9. Measurement and Verification (M&V): Measurement and Verification is the process of measuring and verifying energy and water savings in a building or system. It is used to ensure that energy efficiency measures are achieving the expected savings.

10. Energy Conservation Measures (ECMs): Energy Conservation Measures are actions taken to reduce energy use in a building or system. Examples include installing energy-efficient lighting, adding insulation, and optimizing HVAC system performance.

11. Simple Payback: Simple Payback is a method of calculating the time it takes for the savings from an energy conservation measure to equal the cost of the measure. It is expressed in years.

Challenge: Calculate the simple payback for an energy conservation measure that costs $10,000 and saves $2,000 per year in energy costs.

Solution: Simple Payback = (Cost of ECM / Annual Savings) x (1 year) Simple Payback = ($10,000 / $2,000) x (1 year) Simple Payback = 5 years

12. Life-Cycle Cost Analysis (LCCA): Life-Cycle Cost Analysis is a method of calculating the total cost of owning and operating a building or system over its entire life, including initial capital costs, maintenance costs, and energy costs.

13. Return on Investment (ROI): Return on Investment is a measure of the profitability of an investment, expressed as a percentage. It is calculated by dividing the net profit from the investment by the cost of the investment.

Challenge: Calculate the ROI for an energy conservation measure that costs $10,000 and saves $2,000 per year in energy costs, with an expected life of 10 years.

Solution: ROI = (Net Profit / Cost of Investment) x 100% ROI = (($2,000 x 10 years) - $10,000) / $10,000 x 100% ROI = 100%

In conclusion, energy benchmarking is a critical tool for identifying opportunities to save energy and reduce costs in buildings. Understanding key terms and vocabulary related to energy benchmarking, such as EUI, weather normalization, source and site energy, Energy Star score, ENERGY STAR Portfolio Manager, ASHRAE Levels I, II, and III energy audits, IPMVP, M&V, ECMs, simple payback, LCCA, and ROI, is essential for energy auditors to effectively measure and track energy use and identify energy-saving opportunities. By applying these concepts, energy auditors can help building owners and managers reduce energy costs, improve energy efficiency, and contribute to a more sustainable future.