How do we ensure that humanity flourishes in the cities of the future?
At the first Digital Cities Summit, dozens of researchers, entrepreneurs, and policymakers participated in a two-day conversation spurred by one of the 10 urgent challenges recently put forth by the Stanford School of Engineering: How can engineering ensure that humanity flourishes in the cities of the future?
It’s a pressing question that will only grow more urgent, said Dean Persis Drell in her keynote introduction. More than half of humanity already lives in cities, and as urban areas become more populated new challenges will arise for an array of infrastructure systems, from housing and water treatment to power and telecommunications. Drell spoke about how new technologies and advances can “help governments and private companies better address these unmet needs, and hopefully make infrastructure services even more robust and accessible.”
Several kinds of next-generation urban infrastructure systems – including telecommunications, power generation and waste treatment – are evolving from centralized infrastructure systems toward smaller, decentralized systems that have no “last mile” of pipe or wire and hence need no longer be regulated as natural monopolies. As a result, they can be financed privately by long-term investors such as pension or sovereign funds, and they can be furnished and operated by private firms with limited regulatory oversight. In addition, these decentralized systems can be instrumented at exponentially lower cost over time to yield streams of valuable data for use by cities and companies in providing more accessible, efficient and sustainable infrastructure services to their citizens.
In a series of talks, Stanford Engineering researchers presented an array of such insights and innovations, and discussed how they might shape the future of the hardware infrastructure that undergirds life in urban centers.
A glimpse of what 100% renewable energy would look like
It’s impossible to think about the future of cities without considering the future of energy. Civil and environmental engineering professor Mark Jacobson, who has done some ambitious thinking on just that subject, laid out a vision for how the U.S. can transition its entire energy infrastructure to run on clean, renewable energy by 2050.
It’s a Himalayan-sized goal, yet one that would require no new technologies to summit, he said. In particular, his research illustrates the hidden upside of using solar, wind and water resources – rather than burning fossil fuels – to power everything from appliances and machinery to cars and building systems. “If you electrify everything, something magical happens. Without really changing your habits, you can reduce power demand by about 42 percent,” he said.
That huge reduction in power demand comes mostly from the efficiency gains of electricity over combustion and eliminating the energy needed to mine, transport and refine fossil fuels. All told, Jacobson estimates that instead of the 20 terawatts that we are projected to need in 2050 using our current energy mix, converting to 100% renewable energy would slash power demand to around 12 terawatts. And that’s just the pure energy savings. Jacobson also estimates that we could avoid 4 million to 7 million deaths from air pollution, eliminate $15 trillion to $25 trillion in global warming costs, create 17 million more jobs than would be lost if we don’t transition, and reduce the energy poverty of up to 4 billion people worldwide.
A simple change to permitting policies that could help clear an energy-efficiency obstacle
Buildings account for nearly 40% of the energy consumed in the U.S. In densely packed urban areas like New York City, it’s even higher, and up to 75% of greenhouse gas emissions come from energy used in buildings. In fact, as part of a comprehensive plan to protect the quality of life for current and future residents, New York has pledged to reduce emissions by 30% by 2030. Work by assistant professor of civil and environmental engineering Rishee Jain in the Urban Informatics Lab highlights how data that’s already right at our fingertips might help meet that challenge today.
To get a sense of the roadblocks hindering greater clean-energy adoption in urban areas, Jain analyzed data collected by the city of New York – including when fuel oil is delivered to buildings each month and a host of other characteristics such as building size and value – and built an algorithm that he summed up quite simply: “Instead of finding communities of people who have similar features, we looked for communities of buildings.”
He found matching clusters in the wealthiest neighborhoods of the Upper East Side and the poorest neighborhoods of the Bronx. Despite the similarities, however, the roadblocks to implementing adoption of cleaner fuel were quite different. His team hypothesized that while typical capital constraints hindered financing clean-energy projects in the Bronx, the challenge in the Upper East Side was shaped by policy. Building managers were scared to start a project over the summer because the permitting process was so long and onerous that, come a cold snap in October, they feared not being able to deliver heat to their high-profile occupants and perhaps risk their jobs.
This data-driven insight revealed an unexpected way to spur the adoption of cleaner fuels. In this case, Jain said, a simple change to permitting policies around when a project can start could help clear an energy-efficiency obstacle that otherwise might have remained hidden in plain sight.
From cracking pipes to smart sewers
While most of our interactions with the urban environments of the future will happen above ground, civil and environmental engineering professor Craig Criddle has his sights set lower, to our aging wastewater treatment systems.
While discussing the process of re-inventing the wastewater treatment plants and sewers of the 20th century – many of which are nearing the end of their 40-year life cycles – into more dynamic water resource recovery centers, Criddle outlined how new wastewater management strategies will provide abundant new sources of energy, materials and even information.
Traditional wastewater treatment is an energy-intensive endeavor, and handling the residual solids can be a huge problem. But there are some enticing possibilities if we can reframe how we think of the process, Criddle said: “Can we turn a liability into an asset? Can we turn wastewater into something valuable? One thing we can produce is clean water; another is energy.” The Codiga Resource Recovery Center at Stanford, a new pilot-scale testing facility, features anaerobic biotechnology that produces clean water with few biosolids while also producing rather than consuming energy.
“What else can we make and sell in addition to water and energy?” Quite a bit, he explained. It’s possible to produce compost, bioplastics, and fish food. Beyond that, he said, there’s even a potential for recovery of a trove of information.
To recover this information, Criddle is working toward “smart sewers,” where monitoring enables quick detection of leaking pipes. In addition, DNA and RNA extracted from wastewater give insight into pathogens, antibiotic resistance and other measures of community health. “It remains to be seen how valuable that information will be financially,” Criddle said. “But we believe it will be very valuable for protection of public health.”
