Net-zero energy buildings and whole system energy solutions were just a couple of the topics at Danfoss’ 19th EnVisioneering Symposium. The event, titled “Building and Energy Infrastructure,” was held June 5 in Washington, D.C.
The symposium brought together several experts and leaders from HVAC equipment manufacturers, building consultancies and contractors, utilities, advocacy groups, and experts in research and policy, to explore new opportunities in next generation energy technology for commercial buildings.
Thomas W. Hicks, deputy assistant secretary of energy for the Navy, was the keynote speaker. He outlined the Navy's goals, strategy, and practices for energy use and energy efficiency. The U.S. Navy maintains global operations relying heavily on foreign energy and is dependent on the ready availability of energy and fuel. But the Navy's access to energy is subject to both price and geopolitical volatility — forces that impact the entire building market but have recently hit the Navy with special force.
In response, the Navy has set energy goals that include operating 50% of its installations at net-zero energy by 2020. Among its steps to achieve that goal, Hicks described a Navy turning increasingly to micro-grid technology.
“We need to take the cost advantages from smart grids — and demand response and demand reductions — and marry those with the security benefits we might be able to get from micro-grids,” Hicks explained.
Stephen Selkowitz of the Lawrence Berkeley National Laboratory was also a guest at the Danfoss event. He spoke about energy efficiency, and pointed out that efficiency gains in the U.S. economy since the 1970s are already saving $700 billion a year. However, he foresees that making the basic changes required for highly efficient holistic buildings would save an additional $200 billion a year, but also requires a major communication effort to fully implement new research and development findings.
“To routinely deliver high-performance, low-energy buildings, we must find a balance between people, policy, markets and economy, innovation, technology, and process,” he said.
Central to achieving that balance is the challenge of communicating the benefits of strongly integrated systems in a way that includes improved occupant comfort, satisfaction, and performance.
To help address that challenge, Richard Lord of Carrier Corp., and Drake Erbe, vice president of market development of Airxchange, presented a report that represented the culmination of nearly a decade of work on the possibility and value of an integrated whole-building design, delivery, and maintenance strategy.
Erbe and Lord outlined the challenges of “max tech.” They said the cost of improved efficiency is becoming prohibitively high, the added gains are getting smaller, and most decisively, the very possibility of improved efficiency is coming up against absolute limits imposed by the laws of thermodynamics. There is little efficiency yet to be gained through a component-based approach, and much is at a cost the marketplace will not accept.
Whole systems and hybrid sub-systems, however, offer a new opportunity. A relatively simple hybrid system illustrates the broader concept. Two or more technologies are combined in a system design. Then, during the course of the annual use cycle, each technology is activated when it delivers the most benefit. It is, of course, necessary to design some type of combined rating system to assess overall performance, but technologies as diverse as airside economizers, hydronic economizers, integrated exhaust air energy recovery, evaporative condenser, evaporative precoolers, and solar assist units can be brought together to achieve systemic efficiencies far beyond the reach of improved components and be more cost effective.
Metrics for such innovations are not yet generally available, but steps are being taken. As Mick Schwedler, manager of applications engineering at Trane, suggested, it is critical that new metrics be selected carefully so that the right behaviors are encouraged. One example is the Air-Conditioning Heating and Refrigeration Institute's Guideline V that provides a full load rating for a combination of an air cooled packaged product, and an energy recovery device. While only a full load metric is now available, work has already begun on one for part load, and many systems could benefit from similar efforts.