With important legislation for energy efficiency and climate change sitting on Capitol Hill, HVACR industry experts gathered May 13 at the Library of Congress in Washington, D.C., to discuss the technologies and strategies needed to engineer and construct net zero energy buildings.
More than 50 industry professionals participated in the 13th Danfoss EnVisioneering Symposium, which included presentations from the following speakers:
- U.S. Congressman Steve Israel (D-NY)
- U.S. Congressman C.A. “Dutch” Ruppersberger (D-MD)
- James Rannels, supervisor, Commercial Building Integration and Deployment Project, U.S. Department of Energy, Bureau of Energy Efficiency and Renewable Energy
- Richard Lord, engineering fellow, Carrier Corporation
- Drake Erbe, vice president, market development, Airxchange, Inc.
- Karen Penafiel, CAE, vice president for advocacy, BOMA International
- Godfried L. Augenbroe, associate professor, School of Architecture, Georgia Institute of Technology
- James McClendon, director of engineering, Wal-Mart.
In his opening remarks, Robert Wilkins, president, Danfoss North America, said, “The current trajectory of technology-based energy efficiency improvements seems unlikely to meet important energy savings goals related to cost, global security, energy security and climate change. Progress is being made, but the trend does not match the challenge.”
“Energy is a critical and urgent issue related to national security, our national and world economy and is a global environmental issue that is not likely to be solved in a business-as-usual fashion," Wilkins said. "We at Danfoss are increasingly convinced that it is time to ask some big practical questions—about limits, basic definitions, possibilities, roles and requirements—that will help us to evaluate the potential of an approach to energy efficiency that would constitute a serious departure from today’s standards.”
Systems Approach
Sticking to the symposium’s theme, “Rx: Systems Approach to Net Zero,” Drake Erbe of Airxchange, Inc. introduced the idea of a systems approach to energy efficiency.
“The building delivery system must be driven by more than just manufacturing,” said Erbe. Together with insights from Richard Lord of Carrier Corporation, Erbe emphasized that components have been nearly maxed out in terms of energy efficiency. They said each building needs to be approached from a systems level, and, more importantly, building components and systems need to be integrated to work together, and improve energy efficiency.
“If the desire is to be at net zero by 2030, efficiency requirements also need to change,” said Lord. “As they stand today, they do not recognize or reward innovative designs. The fact is that operations cannot be controlled independently—for example, heating systems should recover energy that can then be used for other building systems. We are currently defining efficiency based on components, and we need to develop a different approach to reach efficiency goals.”
Wilkins said a systems approach, “requires us to look at more than just individual pieces of equipment. By integrating heat recovery technologies that match output to load and renewable sources—located both onsite and remote, such as solar PV panels, wind and geothermal, we then can add energy-efficient equipment to a system designed to maximize building function.”
As the symposium’s participants pointed out, most buildings are not operated as intended, which ultimately affects energy efficiency. Instead, operations and maintenance need to go hand-in-hand with energy engineering. In order to achieve this partnership, the industry needs more than voluntary standards; enforceable standards should be used to achieve and guarantee maximum results.
The Role of Emerging Energy Efficiency Policy
In this second session of the symposium, James Rannels, U.S. Department of Energy, defined net zero energy buildings (NZEBs) as buildings that produce as much renewable energy as the building uses annually. This includes energy-efficient improvements that reduce energy consumption by 60 to 70% over existing standards and implements renewable sources to supply the balance of any energy needs.
“The greatest potential for energy savings is in commercial buildings,” Rannels highlighted. In 2006, buildings accounted for 40% of U.S. energy use, 18% of which was in commercial buildings. Today, the U.S. Department of Energy has partnered with more than 20 companies in the retail, hospital and commercial real estate arenas to form the Commercial Building Energy Alliances (CBEAs), which have jointly agreed to each build one new building at 50% less energy than ASHRAE Standard 90.1 and retrofit one building that uses 30% less energy.
Karen Penafiel of BOMA approached the issue of creating NZEBs from the perspective of the building owner/operator and raised concerns about the cost of building codes and benchmarking energy efficiency.
“National building codes can be very restrictive to many building owners and managers,” Penafiel said. “When specific energy-efficiency standards are mandated—for example, a 30% reduction in energy use, building owners who are unable to fully meet those strict requirements can, as that information is made public, actually become vulnerable to scrutiny and additional costly mandates such as energy audits.”
Her argument comes at an appropriate time, as legislation structured to increase energy efficiency has been on the rise over the past year. Both Penafiel and Israel expressed concern that, while the country has been focused on top-down investments in energy efficiency, the focus should be on bottom-to-top investments, encouraging Americans to realize a need for energy-efficient technologies in their own homes first and foremost. PACE (Property-Assessed Clean Energy) bonds, Israel said, could play an important role in incentivizing Americans to upgrade their homes to include these energy-efficient technologies through government-funded loans.
Bringing Energy-Efficient Building Systems to Life
The attendees stressed that true energy efficiency and net zero will require more than just policy; it will require the architect and the engineering teams to work as a whole to design buildings that ensure optimum systems are put into place.
“Getting to net zero will require a focus on more than just component scale optimization,” said Godfried Augenbroe, associate professor, School of Architecture, Georgia Institute of Technology. “Architects and engineers will need to rely on the concept and how systems work optimally together in order to achieve net zero building design. The key, though, is to not over-engineer the energy model. Think about uncertainties in your assumptions, and then model these uncertainties explicitly, tying them to risk analyses and cost analyses,” Augenbroe continued.
“Separate systems—such as energy, controls, airflow and communications—create failing buildings. Figuring out how these total systems integrate, through design, function and control, will help to achieve maximum energy results,” Augenbroe said.
This raised the question of existing and pending LEED-certified buildings that either cease or fail to meet performance requirements and whether the problem lies within the building or the model itself. As an example of a systems integration approach to energy efficiency, James McClendon, director of engineering, Wal-Mart, introduced the retail giant’s “non-conventional approach to building and campus design.”
Wal-Mart’s new prototype stores include high-efficiency lighting, doors on refrigerator cases, solar panels and onsite wind turbines, which have proven a 27% reduction in energy use and significant reductions in refrigerant use over the company’s existing stores.
“In evaluating our stores globally, Wal-Mart has relied heavily on benchmarking as a critical first step in developing high-performance buildings,” said McClendon. “But the real key to success has been the ability to look beyond programs for buildings and instead create building programs. As mentioned previously today, component optimization is a must, but it will only take us so far in the goal of energy efficiency and net zero.”
In his concluding remarks, Wilkins stated, “While net zero might sound like a far-fetched concept, this Symposium has helped to lay the groundwork for a convincing story that serves as a practical long-term target, and that, even today, we’re capable of making dramatic steps in that direction. American innovation is resilient, but political gridlock is hampering progress and change. Innovation within our industry has proven its ability to rebound and prevail time and time again, but regulatory government support is needed if we truly wish to see greater strides made in energy efficiency and the goal of achieving net zero energy buildings as an everyday reality.”