by Warren Karlenzig
One of the great challenges in urban planning and green building has been material life cycle energy use--how steel, concrete and wood products were produced and transported. Add to that the decisions people make once construction is finished, and you can rightly conclude that development standards have only scratched the veneer of total energy and sustainability impacts.
In addition to material climate and resource burdens, there are myriad consequences on life-cycle energy use that arise from commuting and transit choices, food and product consumption, and building heating or cooling.
Scientists at the US Department of Energy's Lawrence Berkeley National Laboratory (LBNL) have devised a tool that may soon provide governments and urban planners ways in which to model complete material, building and residents' anticipated energy use.
After a proof of concept was applied to a Jinan, China, housing development, LBNL has integrated building life-cycle assessment (LCA) and urban form agent-based modeling tools to capture embodied, operational and behavioral aspects of urban form energy use and emissions.
With hundreds of new cities being planned or built in China, Indonesia and India, new tools such as LBNL's will be critical is managing and reducing the energy, climate and environmental impacts of this unprecedented urban growth era.
Adding 1.1 billion people to new or growing Asian cities will produce more than half of the world's increase in global climate change-causing greenhouse gases by 2027, according to the Asian Development Bank.
I met last week in the green hills of Berkeley with David Fridley, Nate Aden and Yining Qin at LBNL's China Energy Group offices. The team demoed their new urban form and behavior energy analysis tool, describing how they based its performance on a variety of existing approaches in urban form-related analysis and life-cycle materials analysis.
The innovative aspect to the group's project is that they combined these existing cutting-edge approaches with an extensive survey of 230 residental households in the Lu Jing Superblock.
The researchers examined where Lu Jing Superblock (built in 2008) residents worked and went to school, how they commuted, where they shopped, what kinds of appliances they owned and how they used them, and even how much meat and what kind of products they ate.
The result was perhaps the closest-yet attempt at modeling and thus being able to forecast the complete energy needs of a segment of urban population. This allows an integrated assessment of required energy supply and expected impacts far beyond a single structure, energy type or industry.
It's like Sim City, but for addressing real planning, energy, and environmental challenges, which is something I've always wanted to see.
Simulations ran through the four seasons, showing cumulative energy use based on household and individual appliance and transportation use, showing cars or buses shuttling between supermarkets, offices, schools and the Lu Jing Superblock.
Total energy use and types of energy used were continually graphed, and the final results showed a breakdown between how much energy would be used by the buildings for power, cooling and heating, as well as for transportation, food and other areas.
The group sees the tool being used by policymakers trying to prioritize energy and climate regulations in land use, transportation, planning and energy. Urban planners are another obvious group of potential end users.
One planning issue unresolved for future iterations of the tool would be how water use and supply could be added to the analytical capabilities. Or perhaps LBNL's energy tool can be combined with a software-based supply analysis and use forecasting tool for water. Water life-cycle analysis is an especially relevant issue when planning development in areas of India and Northern China that are facing climate-related drought and water supply shortages.
Still, the LBNL effort is significant in synthesizing existing tools and approaches on urban energy use into a single model that can help guide our world as we move into what is increasingly becoming the century of urbanization.
Warren Karlenzig is president of Common Current, an internationally active urban sustainability strategy consultancy. He is author of How Green is Your City? The SustainLane US City Rankings and a Fellow at the Post Carbon Institute.
Energy modeling for buildings is complex enough, and a similar idea applied to entire cities is a pretty incredible prospect if it too can be used to inform better designs - and induce behavioral changes. While important, in recent years measuring carbon emissions seems to be the test of sustainability. But really it's going to take more comprehensive and integrated data like this to develop policies that are going to change the inner workings of our expanding cities.