New approach converts disparate units of measurement to a common measurement unit making it possible to compare sustainability of different buildings.
By: Jennifer Call and Ory Zik
Owners, managers and occupants of buildings that want to improve their sustainability face a difficult challenge. There are a number of different ways in which buildings impact sustainability such as their electricity usage, natural gas usage, fuel oil usage, water usage, etc.
Today buildings can easily optimize each unit separately with increasing resolution but don’t have a way to translate across domains as is needed to make decisions to improve sustainability. For example, what has more impact on sustainability: implementing displacement ventilation vs. converting from fuel oil to natural gas vs. adding insulation, etc?
Nor is there a way to compare sustainability of buildings serving different functions or different locations. How do you compare the sustainability of a medical office to a factory making contact lenses? Or how do you compare a medical office in Michigan to one in Arizona, where use of a given amount of water has a much greater impact on the environment.
Many building owners use a strategy of reducing expenses but the reality is that price signals are often opposite to sustainability. For example, water in Albuquerque, NM costs less than half what it does in Minneapolis, MN even though precipitation is much higher in Minneapolis.
More and more building owners, managers and occupants want to optimize the sustainability data stream with increasing granularity. They understand that increasing sustainability not only reduces the impact on the environment but also reduces risk that prices and regulations will change to reflect scarcity. Sustainability is a key performance indicator of the future, second only to financial performance, yet there is no quantitative way to translate between domains in order to set and meet quantitative goals.
Zik Energy Points has developed a simple, intuitive quantification system based on the amount of energy consumed over the full lifespan of a process or object. The unit of measurement is the amount of energy embodied in one gallon of gasoline, an Energy Point (EP), which basically works like diet points but for sustainability. Power generation, buildings, manufacturing processes, water, waste or anything that consumes energy can be measured using EPs.
The metric is easy to understand because people understand the cost and characteristics of gasoline intuitively. Water is quantified as energy by incorporating all of the energy needed to extract the water, including the infrastructure, while factoring in the embodied energy of the infrastructure and the geographical scarcity of water. For example, water production, distribution and treatment use less energy in Minnesota than New Mexico, even though water costs less in New Mexico.
Sustainability of 22 buildings measured in terms of EP/square foot.
Energy Points were recently used to measure the sustainability of 22 buildings in the New York City area. The study included many different types of buildings including manufacturing, residential, warehouse and other commercial space. This work was done in collaboration with Living City Block in Brooklyn, New York. Conventional approaches of comparing their electricity, natural gas and water usage would have had little relevance to sustainability due to their widely different functions and building systems. But the Energy Points system made it easy to measure the overall sustainability of each building in Energy Points per square foot. The results are shown in the figure. Outliers in the current example include a dry cleaner (Building E) and residential building that provides healthcare services (Building M).
Posted: 11/17/2011 1:38:25 PM by
Mary Kestner | with 0 comments