High LEED, HERS, RESNET and Energy Star building construction scores are cool energy efficiency certifications to strive for if you are a sustainability nerd, or if you are looking to save money. Yet, those certifications only prove that your building has the ability to be energy efficient. They don’t guarantee that your building is actually using less energy than older construction methods. The hard work of saving energy starts when people actually take occupancy of buildings.
R-value of windows doesn't matter if those windows are open all winter. A Vorando Reality Trust study found that tenant activities are responsible for 60 to 80 percent of a building’s energy usage. A super-efficient building with wasteful tenants might be worse than a leaky warehouse with attentive tenants,
How do you keep track of the energy your building is using after tenants move in? LEED has introduced their Dynamic Plaque to help you keep track in real time. The plaque has a screen that gives your building an ongoing 0-100 score. The goal is to engage tenants. If you turned the air conditioning down to 60°F and opened all the windows, you would watch your energy score on the plaque drop, theoretically.
But, there are lots of new ways to keep track of your building’s performance. Some of the options are a couple of hundred dollars; some fully automated systems could cost hundreds of thousands. Overall, even if you have only basic feedback on your water, electricity and gas consumption, you will be able to make informed decisions to and change them notice and change wasteful trends. Most people get high utility bills and have to guess as to what caused the number to be so high.
As with finance, it is great to know where every penny goes in the span of a month, but it is better to be able to pick out the larger trends and notice important changes. Find the key data. Did this building use more energy this January than it did last January? Do we have a water leak somewhere in the building?
I recently worked on a job where they insisted on data points for anything and everything that moved in the mechanical room. Having lots of data is only good if you can make sense of it. The property manager knew that if the icons stopped spinning, the pump was not working, but that was about the extent of the analysis. Before you write a check for any energy monitoring system, sit down and decide what information you would want or need to know.
From a contractor’s standpoint, you can help troubleshoot a system if you know energy and water use trends. If a customer could receive an alert when their water usage is spiking, they could call you to come and investigate before they get a thousand dollar water bill. Maybe a pipe froze in the attic because someone left a window open in the garage before they left for vacation, and water began flooding and freezing on top of their Porsche (true story).
We once had a job where the customers had a particular zone that struggled to heat above 60°F. We went through the controls and boiler settings to find a reason why this was the only zone that wasn’t heating well. Luckily, we had a data logging thermostat system installed, and we eventually looked at the graphs. The thermostat would call, the boiler would ramp up to the design temp, and the zone valve would stay open all day. We didn’t have a flow issue, we had an undersized hydronic fan coil. It was getting its design supply temp all day and couldn’t keep up. Without the data logging, it would have been difficult to prove with hard numbers that the fan coil was too small.
If the building you are in charge of isn’t a single-family dwelling, it's useful to monitor multiple data points. Multi-occupant buildings use an enormous amount of energy and most of them simply split the energy bill per person or tenant. The likelihood of that being the just way to bill your customers is low.
A New York State Energy Research and Development Authority study of multi-family buildings found that 10 percent of the apartments in the group of buildings used about 20 to 25 percent of the building’s electricity. Most of the tenants used less than what the average would have been if the utility bill was split evenly between all the occupants. If nobody is keeping track, people will waste energy. As soon as tenants get a bill for their actual consumption, the usage goes down.
Sub-metering isn’t a new concept. According to a 2011 report by the National Science and Technology Council (NSTC), “In 1977, the city of Boston, Massachusetts, could not account for the use of 50 percent of the water used in its municipal water system. After installing meters, the city undertook a vigorous leak detection program. Water that was unaccounted for dropped to 36 percent after metering and leak-detection programs were started.”
The same NSTC report contains multiple case studies. Not every building would benefit from super-precise energy metering if the cost of the meters was more than a few years of the utilities they are monitoring. However, Adobe Systems Inc., and Southern Connecticut State University used energy metering to gain information about their mechanical systems and found their payback to be less than a year for certain upgrades of wasteful equipment.
I heard a story of an apartment complex that had enormous water bills. They eventually found that one of the units was running their shower for hours at a time. Those particular renters were sensitive to the low humidity, so they let the shower run continuously to help humidify the apartment. For them, it was less expensive than buying a $40 humidifier.
If energy or water is at a very high premium, people may use technology to tell on you for being wasteful. In California, people are using the app VizSAFE to “drought shame” fellow citizens. If you walk past a business watering their lawn in the middle of the day while in a record drought, you can post a photo of that business on a searchable map for the world to see.
In Nevada, “water cops” can take a photo of your water waste from the sidewalk and send you a bill. As of last year, officials had the ability to hand out $500 fines. Nevada Governor Jerry Brown favors fining the worst of the worst water wasters up $10,000, according to the Las Vegas Sun.
Whether you are using energy metrics to lower your propane bill, or to embarrass your neighbor on the Internet, there are lots of new ways to do so. It is odd how impactful simply knowing what energy you are using can be surprisingly valuable. Reducing energy first seems to run contrary to the American inclination to simply get more energy. As the satirical website, The Onion, put it, “Scientists Continue Developing Alternative Energy Sources For Americans To Waste.”
Max Rohr has worked in the hydronics and solar industry for 10 years in the installation, sales and marketing sectors. Rohr is a LEED Green Associate and is Radiant Professional Alliance’s (RPA) Education Committee Chairman. He can be reached at firstname.lastname@example.org and @maxjrohr.com.