What is the Biggest Culprit? Concerns about the impact of energy consumption on the environment, especially global climate change, have finally penetrated public consciousness to the point where significant political action is beginning to happen.
Any number of events can be cited as triggering this step change in consciousness. Al Gore’s movie An Inconvenient Truth, numerous cover articles by our leading weekly magazines, a continuous stream of newspaper articles, scientific reports from prestigious committees, appeals to the President by business leaders, politicians, and scientists, etc., have outlined the risks and challenges to the planet in compelling detail. As Governor Arnold Schwarzenegger commented when he introduced Executive Order S305 on greenhouse gas reduction, “I say the debate is over. We know the science. We see the threat. And we know the time for action is now.”
The question is: where should we focus our efforts? We can begin by asking: where are the biggest culprits and what are the most immediate cost effective strategies, but the challenge is more fundamental than the idea of mitigation or conservation, as important as they are. Ultimately, we must rethink and convert our 200-year-old fossil fuel economy to renewable sources. An even more fundamental question is: can we do it in time to avoid catastrophic change and human hardship?
The recent announcement at UC Berkeley of a $500 million grant by oil giant British Petroleum (BP) to develop biofuels is not only by far the largest alliance between industry and the academies, but also the kind of investment and vision necessary to bring renewable energy swiftly to market. BP’s grant will fund hundreds of researchers in 25 teams, 18 at UC Berkeley and Lawrence Berkeley National Laboratory (LBNL) and 7 at University of Illinois Urbana-Champaign, while BP will assign up to 50 of its own researchers to join the teams. The potential of this landmark interdisciplinary effort is planetary. LBNL Director Steve Chu has estimated that if the acreage which American farmers are currently subsidized not to cultivate were planted in “switch grass” and if ethanol from this cellulose source could be brought to market at the efficiencies demonstrated in the lab, it could provide as much as 100% of the country’s transportation fuel needs. UC Berkeley Chancellor Robert Birgeneau has characterized the effort as “our generation’s moon shot.” Charles Zukoski, Vice Chancellor of Research at the University of Illinois Urbana-Champaign, described it as launching “a new age for agriculture, altering the energy economy of the planet.” As essential and groundbreaking as this effort is, how big an impact will it have on the problem?
An examination of our energy consumption by broad sectors reveals the following approximate breakdown: 27% transportation, 30% industrial, 22% commercial, 21% residential. Almost all the energy consumed (90%) comes from fossil fuels, with the remainder from nuclear and renewables, including wind and hydro. When each sector is examined in greater detail, some surprising facts are revealed. Within the transportation sector, only 16% is consumed by cars and trucks, the remaining 7% goes to trains and planes. Thus, if all the transportation fuel for cars and trucks (as big a number at that is) were converted to biofuels, it would still only address 16% of the problem. So what is the biggest culprit?
As Ed Mazria has pointed out in his “2030 Challenge” to design and construction professionals, if you add up the residential and commercial sectors with the portion of the industrial sector consumed by buildings, it totals 48% of the total energy consumption! If you look at electric consumption by itself, 75% goes to operate buildings. With the projected increase in electrical demand planned to be met by coal-fired power plants, the impact of buildings is even more important. Quite simply, buildings are both the biggest problem and opportunity.
Mazria also points out that over the next 30+ years, we will build approximately half again as much new square footage as already exists and we will renovate about 50% of the existing square footage. This means that in the year 2035, three quarters of the built environment in the U.S. will be either new or renovated. This gives design and construction professionals the largest responsibility for making a real difference, but as Schwarzenegger has said “the time for action is now.”
We know from over 30 years of research and development since the last oil crisis in the early 1970s, that we can reduce the energy consumption in buildings by 50-70% through intelligent conservation and the application of passive solar heating, natural ventilation and careful daylighting. The question becomes how do we get the rest of the way to zero carbon buildings — i.e., buildings which generate all of their energy needs from renewables. This is the “moon shot” challenge to design and construction professionals.
With the loads for heating, cooling and lighting reduced dramatically by the strategies above, the remaining challenge is the electric loads for building equipment, appliances and especially the so-called “plug loads” for computers, televisions, kitchen and office equipment. Conservation in lighting and appliances, especially refrigerators, are the reason why electric consumption in California has been flat for the last 20 years in spite of population growth. This phenomenon has been called the “Art Rosenfeld Effect” because he pioneered the “energy star” rating system for all appliances, especially refrigerators. Natural competition in the market place, as a result, reduced energy consumption by 50%. His colleagues at LBNL pioneered in the development of high efficiency light bulbs with a similar result.
To achieve the goal of zero carbon buildings, the country will need the next generation in conservation technologies in all areas of electric usage, including lighting, appliances, televisions, computers, etc. Fortunately, many of these technologies are in the development phases and are on the way. As demonstrated in California by the “Rosenfeld Effect”, conservation will remain the single most cost effective first step. Nonetheless, buildings will still require electric power; even with reduced loads, and the challenge is can it be met by renewables?
Through our research at the college on the application of photovoltaics and wind technologies to buildings, we have discovered recent commercially available breakthroughs which are extremely promising. By integrating photovoltaics (PV) directly into building assemblies, like roofs and curtain walls, i.e., substituting existing materials with PV materials, the cost effectiveness of PV is already competitive in some markets, especially when compared with peak power. When the next generation of efficiency achieved in the lab (20%-40%) is brought to market in 3-5 years, the integration of PV into building assemblies should become a matter of course for designers.
The story about the integration of small-scale wind machines into building design is equally promising. A new generation of vertical axis machines, double-helix spiral-like rotors, seems to have solved many of the prior problems. Quiet, non-vibrating, effective at low speeds and multi-directional, their applications on roofs and facades offers multiple design opportunities.
When both of these technologies are combined, we have discovered that they have the potential of providing more than 100% of the total electric loads, on an annual average basis, after careful conservation. Yet, the final challenge is overcoming the intermittent timing of these renewables. What do you do if there is no sun and no wind, and you are unable to capture excess energy (when available) by running the meter backwards, i.e., using the grid as storage?
The final step to zero carbon buildings, for instance providing the backup to wind and solar, comes from a surprising source — the waste streams. In our research work on sustainable neighborhoods in China, we have discovered that food wastes, the sludge from primary sewage treatment and green wastes from the landscape, urban gardening and agriculture together generate a significant energy resource in the form of biomass. New technological breakthroughs in biogas generation use a two-stage anaerobic process to convert as much as 80% of the potential energy in the biomass into biogas — methane and hydrogen. This energy source can be put to many uses, for example: providing gas for cooking, compressed gas for gas-powered vehicles, or powering gas-electric turbines for the base or back-up electric loads.
For this technology to be cost effective, however, it needs a minimum flow of biomass material equal to about 8-10 tons per day, or the waste created by a mixed-use, high density neighborhood of approximately 5,000 units of housing (15,000 people). While the construction of such a neighborhood is the exception in the U.S., 10-15 of these kinds of neighborhoods are completed every day in China. We have discovered that the three renewable energy sources, wind, solar and biomass together can provide all the energy for such a neighborhood. Indeed, the neighborhood can be a significant energy exporter to the grid — especially at peak demand during summer afternoons. The challenge of realizing such an integrated and self-sustaining system of energy supply is that it requires a whole new way of doing business for the design and construction industry. The developer, architect, landscape architect, civil engineer, mechanical engineer, city departments of planning and public works, have to operate under a whole new paradigm of collaboration and integration. But the rewards are planetary; zero carbon neighborhoods could become a reality.
In the end, the goal of achieving a carbon neutral future in the building sector is at least several years off, at the building scale. It will take multiple technology breakthroughs in all areas of energy conservation and renewables before the building will be an appropriate scale for supplying all of its own energy needs. On the other hand, a carbon neutral future is already achievable at the neighborhood scale. The question is: will planning, design and construction professionals seize the opportunity?
At CED we are striving to provide the educational foundation for our students which will prepare them to seize a leadership role in this effort. UC Berkeley tops a short list of institutions with the unique combination of breadth and depth needed to develop innovative design solutions and approaches to public policy. It requires not only the collaboration of multiple faculty in our three disciplines, but also reaching across campus to civil engineering, the energy and resources group and anthropology, listed below. CED is the only school in the country where this new paradigm has a chance of being realized and is exemplified by:
- Elizabeth Deakin and Robert Cervario’s work in transit-oriented development and the making of walkable and bikeable cities with Michael Southworth
- Tim Duane and Randy Hester’s work to reconcile competing demands on the ecosystem on the island of Hawaii
- Judith Stilgenbauer’s work on green infrastrutures — the multi-functional and productive features of landscape
- Galen Cranz’s examination of the social and cultural bases of a sustainable lifestyle
- Our building science faculty – Cris Benton, Gail Brager, Ed Arens, and Susan Ubbelohde — work on energy conservation, daylighting, lighting controls, interfloor mechanized systems, dual mode buildings and user response to environmental quality
- Our collaboration with The Berkeley Institute of the Environment (BIE) and Energy Resources Group (ERG) faculty – Inez Fung, Dan Kammen, et.al — on renewable energy systems, solar, wind, and biomass
- Anthropology Ph.D. student Shannon May’s work on the post occupancy evaluation of China’s fact eco-village
The greatest challenge is developing the institutional structure and pedagogy to create an effective framework for this interdisciplinary collaboration to flourish. The impact that the built environment has on our planet’s future has never been more critical to our survival and presents us with our greatest opportunity for change.