People around the world have been glued to their television sets for more than two weeks to experience the excitement and triumphs of the 2018 Winter Olympic Games. What if we all found energy management as captivating as curling, or efficiency as exciting as skating?
Consumers who monitor energy use quantitatively and seek out new approaches and solutions can reduce energy spend reliably. And with the data generated by smart meters, many utilities today are using advanced customer intelligence to help their customers become smarter and more energy efficient.
This got us thinking – if energy efficiency were an Olympic sport, which buildings would end up on the podium?
Different types of businesses have different energy needs, so it’s important to keep in mind that not all energy efficiency outcomes can be evaluated in the same way. For example, a grocery store that needs to run refrigeration 24 hours per day has a different set of needs than a warehouse with few occupants. And, buildings with the lowest energy use are not necessarily the buildings that are the most energy efficient.
With this in mind, FirstFuel designed three “events” to evaluate building performance across forty-seven different building types (e.g., schools, warehouses, restaurants, etc.) by analyzing nearly 2,000 virtual energy audits in our library. Without further ado, here are the winners.
Event 1: Lowest Electric Energy Use Intensity
Energy Use Intensity (EUI) is the total energy used per square foot of floor space in a year. It is a function of the building’s primary activity and the amount of energy-consuming equipment housed in the building. Everything from refrigeration to lighting to heating and cooling systems impact a building’s EUI.
Gold: Non-Refrigerated Storage Spaces
Large buildings with low occupancy tend to have the lowest EUI because they have less annual electric consumption per square foot. The gold medal goes to storage spaces (warehouses, garages, hangars, etc.) because they are usually not air conditioned or refrigerated, have a low occupant density, and have a large physical footprint.
Silver: Residence Hall/Dormitories
Being on a school or training calendar, most dorms and residence halls use less energy because they are occupied fewer days of the year than other commercial buildings. Additionally, during the school year, the buildings have low occupant density during the day and low electric use at night when residents sleep. Some dorms are not air conditioned at all, and of those that are, use is minimal because the space is not occupied during the hottest months of the year. Additionally, unlike other residential spaces, most dorms do not have cooking equipment or many large household appliances.
Bronze: K-12 Schools
K-12 schools have a shorter year and are closed during the hottest months of the year. When school is in session, occupants typically head out by mid-afternoon, so the buildings are virtually empty by the evening hours when the lights would need to come on.
Judge’s Note: EUI can be a deceptive metric because it does not take into account that all buildings’ energy needs are not created equal. For example, schools that are generally closed during the summer months do not have consistent energy consumption year-round and can skew the perception of what’s “good” versus what’s “bad.” This is why it is important to consider savings potential as an energy efficiency metric.
Event 2: Lowest Overall Electric Savings Potential (as Percent of Total Usage)
Like EUI, overall savings potential is an imperfect measurement of efficiency, but there are a few standout winners. LED lighting retrofits, especially LED conversions, drive significant savings because they can save between 10 and 25 percent of total building usage. Because of this, when looking at a building’s total energy usage, those in which lighting is a smaller piece of the overall puzzle have a smaller opportunity for savings potential.
Gold: Data Centers/Labs
Technology-heavy buildings such as data centers and labs not only have a ton of hardware and security that needs to run constantly, but these spaces often also need climate controls for equipment.
Silver: Fast Food Restaurants
Fast food restaurants are consistently high energy consumers, but for good reason. Industrial size refrigerators, freezers and cooking ranges require constant use, so lighting retrofits have less effect.
Bronze: Manufacturing Facilities
Similar to data centers and fast food restaurants, manufacturing facilities have high equipment baseloads, meaning there is little room for savings.
Event 3: Lowest Operational Electric Savings Potential (as Percent of Total Usage)
When evaluating business performance, it is most useful to look at operational savings opportunities. This removes the effect of LED conversion from the analysis, and instead focuses on no-cost/low-cost efficiency measures. In this case, HVAC and lighting controls – turning down heating and cooling during unoccupied hours, lighting sensors, and economizers that use outdoor air on mild days instead of running air conditioning – drive operational savings. In terms of ranking building types for energy-saving opportunities, it’s a matter of determining which building types are most capable of turning down energy consuming equipment during some time of the day.
Gold: Multifamily Housing/Lodging
Due to occupancy trends, residential buildings cannot be deeply set back on nights and weekends, so their opportunities are slim for HVAC operational savings.
Silver/Bronze: Supermarkets and Refrigerated Warehouses
We have a tie! For buildings with high refrigeration loads such as supermarkets and some food warehouses, refrigeration can be as high as 50 percent or more of annual usage, and there is not a large savings opportunity to set back refrigeration at night.
Ultimately, Everyone’s a Winner
Like judging the perfect skating routine, determining energy efficiency “winners” can be an imperfect science. It is important to keep in mind that building types are not all created equal, but we do know that some warehouses are more efficient than other warehouses, and likewise, some data centers are more efficient than other data centers. Within each building type, there are elite competitors, and audit tools allow us to recognize the most efficient building types so utilities can help improve efficiency where possible all the time – not just once every four years.
By Andrew Klein
Building Energy Engineer
Lead image credit Pixabay.