4 FM quick reads on Energy Efficiency
1. Paths to Carbon Neutralilty
Hello. This is Greg Zimmerman, executive editor of Building Operating Management magazine.
Today’s topic is working to make your organization carbon neutral. Carbon neutrality basically requires a three-pronged approach – with varying ratios of each of the two, depending on the priorities and goals of the organization, its budget, and how fast it wants to declare itself officially carbon neutral.
The first and most important step is to reduce energy use as much as possible. There’s simply no substitute for an energy efficient building. To start, find the easy energy efficiency projects and operational changes that result in the biggest reductions with the best paybacks. Then move towards tougher projects that move the organization closer and closer to as low an energy spend as possible. Truly carbon neutral organizations are net-zero energy organizations, meaning organizations that require no energy from the grid.
A second leg to the carbon neutral stool is generating renewable energy generation onsite. This usually means using photovoltaic panels or onsite wind turbines.
A third option also involving renewables, but this one is a bit more controversial. You can purchase renewable energy certificates (sometimes just called RECs) or carbon offsets. RECs are purchased by the megawatt hour and ensure that even though the electricity is still coming from the grid, the amount of renewable energy purchased actually is being fed into the grid by some other renewable energy source. Besides helping to meet its own carbon neutral goal, purchasing RECs is one way an organization can help promote the gradual marketwide shift to renewable energy without actually generating renewable energy itself.
Carbon offsets are measured and sold as tons of carbon dioxide and can take various forms. It’s important to understand how the carbon offset company reinvests their money. For instance, buying one carbon offset unit may mean that company is planting trees Florida, or it may mean that the company is actually investing in energy efficiency and renewable energy projects. Most would agree that the latter is more useful to the ultimate goal of carbon neutrality anyway – combating climate change.
Consider Solar Shading to Reduce Energy Use
Today’s tip is about techniques for solar shading. In addition to energy efficient windows or glazing, considering using solar shading devices to block solar heat gain. This can help reduce energy use.
The particular type of shading device used will obviously depend on the design of the exterior of the building and the building orientation, but some of the more commonly used solar shading strategies include carefully placed trees, awnings and trellises, overhangs, grille screens and even solar panels. Some more advanced types of solar shading can be programmed to follow the sun, and therefore adjust the shading as the sun moves across the sky. Overall, solar shading should not block heat gain in the winter, if possible, and should be designed to reduce glare. According to the American Institute of Architects, the most challenging exposures to manage are eastern and western exposures from low morning sun glare and late-afternoon solar load and sun glare.
Another strategy along the same lines is using light shelves to reflect light deeper into a facility. This can save energy because fewer energy-using lights are necessary. If you use this strategy, however, be careful to only reflect light, not glare.
Understanding Building Commissioning
Today’s tip involves building commissioning. According to the National Institute of Building Sciences, commissioned buildings use between 8 and 29 percent less energy than their non-commissioned counterparts. Most industry experts see commissioning as a no-brainer, but facility executives often see only the first cost and, therefore, commissioning doesn’t make the final budget cuts.
However, consider working up an ROI based on possible energy savings and longer equipment life. Many utilities and third-party organizations offer grants, rebates or zero-interest loans to help defray the initial cost of commissioning, as well.
There are three basic types of commissioning. The first is new-building commissioning. With new construction, many experts suggest having the commissioning agent on board as early as the schematics phase to help flesh out inconsistencies or problems in the detailed drawings, before they become problems in the built building. Commissioning is a prerequisite of LEED for New Construction, so in order to get any level of certification, the building must be commissioned.
Retrocommissioning is generally understood to mean commissioning an existing building that had never gone through the commissioning process. The idea is to bring facility equipment back into spec and to root out energy-related problems.
Recommissioning, or continuous commissioning, means commissioning a facility that already has been commissioned. Recommissioning should be done at a pre-specified interval – usually once a year or once every other year. You can earn points in LEED for Existing Buildings for a well-developed recommissioning program.