We all hear a lot about smart buildings – so much that you’d think they were everywhere. But when you look at the data, it seems that most buildings are as dull-witted as ever.
Energy efficiency is a core aspect of a smart building, and yet building energy use has risen over the past several years. The United Nations, noting that about 40 per cent of today’s global greenhouse gas emissions come from buildings, is taking on the problem with its new Global Building Network. The network, with Penn State’s Institutes of Energy and the Environment as a lead institution, aims to create an international framework that will make buildings more sustainable, more efficient, and healthier to live and work in.
Standards are clearly important. Issues like ineffective controls and a mismatch between design assumptions and building occupant behaviors deserve plenty of scrutiny. Part of the problem, though, is the persistent issue of performance drift – buildings and building systems should be highly efficient, but performance deteriorates rapidly or never matches the model. To really solve that problem, we need to rethink the metrics we use to measure energy design for smart buildings.
Accountability drives efficiency
Singapore provides an excellent model. It has been rolling out a policy that builds in accountability for meeting carefully crafted performance targets, and the city is already seeing significant success. Singapore started with a standard for cooling systems based on metrics for efficiency rather than gross energy use. This puts the responsibility on the designers: a cooling system can meet an efficiency-based performance standard even if building operators overcool. If the building doesn’t meet that standard, you know the problem is the system, and if it does but still uses too much energy, you know the problem is operational.
As for drift, advanced high-performance systems require monitoring and support to function optimally over time. Singapore addresses this issue by requiring that the system’s design and construction include measurement and verification features. Initial results from Singapore’s shift in metrics are dramatic: cooling systems in existing buildings subject to the standard are demonstrating an average efficiency improvement of nearly 50 percent.
Now Singapore is moving on to overall energy use indices (EUIs) for various building types, along with a simple way to track energy performance. The idea is that with all these guidelines in place, it will be easy to see where performance problems are coming from – the system or its operation – and the route to a more efficient building will be clear.
More ways to inspire action
Another way to encourage accountability is to establish a metric for building efficiency that is relevant for all types of facilities – weather-adjusted BTUs per square foot, for example. That would allow easy benchmarking: publicly rating facilities within their category (data centers, hospitals, office buildings, and so on) would give designers and operators a target and a motivation for working to make them top performers.
Linking energy modeling to energy action would also lead to better performance. Architects now have tools that let them model energy usage in any number of scenarios to see where the greatest savings are. Similarly, building operators can visualize their energy use and the effects of various actions through dashboard tools, but they often don’t take action because doing so seems too complex or disruptive. These visualizations need to be tied to automated optimization software that takes the friction out of energy efficiency decisions.
Visualization and action are symbiotic. Unless dashboards drive actions, they will always be one-dimensional. Conversely, if all you’re doing is acting, you won’t be able to accurately assess the value of your actions or see when things go off track.
Designing for today’s needs, not yesterday’s
Real building efficiency also requires re-imagining building infrastructure with focus on sustainable use. Building components that use the most energy, such as lighting and HVAC systems, often are designed, configured, and used based on the habits of decades past. When that happens, even systems that incorporate the latest technology will use more energy than necessary.
The biggest challenge with HVAC systems – which account for nearly 50 percent of the typical commercial building’s energy use – is that they are more highly engineered and complex than they need to be. They’re also sized to meet maximum peak energy needs, not for efficiency. In the retrofit market, the best we can do is improve poorly designed systems. That’s well worth doing in terms of efficiency results, as the Singapore example shows.
But when designing new buildings, we can and should be asking: What would the perfect HVAC system look like? What would the perfect lighting system look like? How can all the building’s systems connect holistically to eliminate waste? That’s how we’ll get a technical answer to the performance drift problem, along with truly smart buildings.
Bert Valdman is a board member and former CEO of Optimum Energy. This article first appeared at www.facilitymanagement.com.