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Friday, February 5th, 2016
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| 12:00a |
Realizing your true (solar) potential Nations worldwide are increasingly embracing solar power as an alternative electricity source for homes, buildings, and even the grid. Since 2008, installed solar capacity in the United States alone has grown 17-fold, from 1.2 to 20 gigawatts (GW), according to the U.S. Department of Energy.
But do costs outweigh the benefits of installing photovoltaic (PV) systems in every building?
MIT spinout Mapdwell is answering that question by mapping solar potential for entire cities and providing a cost-benefit analysis for each rooftop. On Mapdwell’s satellite-map website, people can click on an individual roof to receive information about installation price, energy and financial savings, and environmental impact.
The idea is to “empower businesses and homeowners with information they need to go solar,” according to the Mapdwell website.
So far, Mapdwell has mapped eight cities across the U.S., including New York, San Francisco, and three in Massachusetts — Boston, Cambridge, and Wellfleet — as well as a few cities in Chile. Mapdwell is currently expanding to include all major metropolitan areas in the U.S. by year’s end.
Results from mapped cities indicate that, in general, solar panel installation is a “good investment” for long-term homeowners, says co-founder and technology co-inventor Christoph Reinhart, an associate professor of architecture and head of the MIT Sustainable Design Lab. “In Cambridge, for example, a good roof will get you your money back within seven years,” he says.
Of course, that’s if you have a “good roof,” Reinhart adds, which depends on a number of factors that Mapdwell takes into consideration. North-facing roofs get less sunlight that those facing other directions, especially south. But the main culprits for lowering efficiencies, Reinhart says, are trees and other sources of shading. “In the summer you want trees to lessen your air-conditional loads. But if your roof is heavily shaded, that’s obviously not good for solar,” he says.
Mapdwell also provides city-level statistics on “high yield” potential solar capacity and other metrics, giving municipalities a clearer picture of the costs and savings of promoting solar power. For example, Mapdwell estimates Boston has about 1.5 GW of untapped solar capacity, Washington D.C. has 2 GW, and San Francisco has roughly 3 GW.
New York City, on the other hand, has a whopping 11 GW solar potential. If that capacity were met, the solar panels would offset carbon emissions equivalent to planting 185 million trees, according to Mapdwell.
Details, details
To map cities, Mapdwell collects data from LiDAR-equipped planes — which survey urban topography using reflections from lasers to map the terrain — along with geographical and weather data. Additional analysis provides a detailed 3-D model of every rooftop layout.
Data is fed into Solar System, Mapdwell’s online mapping platform, which was developed at MIT and provides a higher resolution and greater accuracy than other mapping services, Reinhart says.
On Mapdwell’s website, each rooftop is covered with many color-coded dots that represent open areas for solar-panel installation. They range in color from bright yellow — representing the highest yields — to orange, to brown, which represents decreasing solar efficiency. Users can outline areas where they may want to install panels, or use a default mode that automatically highlights the most “high-yield” areas. They’ll get specific numbers for the costs of installing a system, the payback time in years, the average monthly and annual revenue, and any tax credits earned. Also displayed are the energy savings equivalent to trees planted, offset carbon, homes powered, and metrics such as energy output, panel efficiency, and more.
“It becomes very specific in telling you where to place the systems and what the local payback times are,” Reinhart says. If interested, users can print or share comprehensive reports and contact installers directly through Solar System’s interface.
Strategy, technology, and design
Reinhart started working on Mapdwell’s core technology in 2011, when he became aware of solar-mapping tools that were cropping up for places such as Boston and New York City. “But when you looked in detail at the maps online, you saw funny things happening,” he says. In other words, the algorithms were working solar radiation calculations that were outdated, inaccurate, or wrong.
At the time, Reinhart’s group had been mapping individual buildings for solar potential. Securing funding from the National Science Foundation, they built out this technology to assess solar potential for entire cities, focusing initially on Cambridge — “to be a good neighbor,” Reinhart says. They presented results to the government, estimating that fitting the city’s 17,000 rooftops with solar panels could generate roughly 30 percent of the city’s electricity.
This Cambridge study opened up Reinhart’s eyes to the commercial potential of displaying solar rooftop data for home and business owners — and the importance of software design. “If we showed people what we were using, no one would get it,” Reinhart says, laughing.
Reinhart partnered with co-founder and current CEO Eduardo Berlin, a former colleague at Harvard University whose research centered around information-driven models for sustainability in the real estate market. Berlin worked on the company’s plan and the platform’s concept and design, including the popular color-coded dots. “You get real dollar amounts, which adds to the value of the system, but people process graphical information better than numbers,” Reinhart says. “That color scheme is incredibly important and seductive.”
Their platform landed them unprecedented results in a 2014 case study for Wellfleet’s Solarize Campaign. Within four months, 10 percent of Wellfleet’s households had commissioned a PV system, “which is seven times higher than comparable solarize program results in other Massachusetts communities at the same time, under identical pricing and framework,” according to Berlin.
Using the platform for initial screening, installers presented quotes for 94 percent of sites visited. More than half of these proposals became contracts. That’s the benefit of having detailed information about photovoltaic installations, Reinhart says: “You come to a site, only to be very sure that the site’s good. Then half the time the owner says yes because they already know from Mapdwell how much it’s going to cost.”
Mapdwell is currently scaling to cover large U.S. metropolitan areas in the next few months. Additionally, Mapdwell has developed tools based on its data to lower customer-acquisition costs for solar-power stakeholders “and ignite a market that is ready and eager for much faster growth,” Berlin says.
Back at MIT, Reinhart and the Sustainable Design Lab are now using similar tools for their newest project: a building-energy model of Boston, which estimates the citywide hourly energy demand loads down to the individual building level. “This is where we want to go forward in cities,” Reinhart says. | | 1:00p |
Into Africa Students come to MIT from across Africa, totaling about 3 percent of the Institute’s population. Some of them stay in the U.S. after graduation, but many return to Africa, often as entrepreneurs. What is life like for these “repats,” who seek to build businesses as they reacquaint themselves with their home countries?
That was the subject of a public forum at MIT on Thursday, as a group of entrepreneurs gathered to discuss their motivations and experiences — from the idealism of trying to help their homelands, to the subtleties of fitting back into African society.
For some entrepreneurs, the decision to return to Africa was simple; others surprised even themselves by leaving the U.S.
“I wanted to use [MIT] as a stepping-stone to go back to Africa,” said Claude Grunitzky, founder of the cultural publication TRACE, as well as the TRACE TV network. Grunitzky, a native of Togo, is a former MIT Sloan Fellow, and moderated the event.
By contrast, “To the surprise of my family, I went back to Nigeria,” said Gbemi Munis, a current MIT Sloan Fellow pursuing an MBA. She worked in Nigeria as a senior systems engineer for Cisco.
“For me, going back to Africa is really about making an impact first,” added Joelle Itoua-Owona, a Cameroon native who has worked in finance and is currently president of the Africa Business Club at MIT Sloan.
Wanted: More business ecosystems
The discussion, “Today’s African Repats,” was part of the Starr Forum series of events on global matters hosted by MIT’s Center for International Studies.
Whatever brings entrepreneurs back to Africa, plenty of challenges arise once they are there, from re-acclimating after time away, to breaking down gender stereotypes in business. And there often remains the hard work of building business networks, communities, and innovation ecosystems.
On the gender front, as Munis described it, as a female executive, she often has had the impression that people are surprised by her individual success and are “looking behind me to see, ‘Where’s the man supporting you?’”
Devon Maylie, a former Johannesburg-based reporter for The Wall Street Journal who is now pursuing a degree at the Harvard Kennedy School, observed that there are “a lot of preconceptions” about women, but added that “there is a lot of work to be done on both sides,” among both foreigners in Africa as well as Africans, to chip away those stereotypes.
“I think writing is an important way to do some of that,” Maylie said, referring to her journalistic work.
Grunitzy, for his part, observed that in programs encouraging entrepreneurship in which he has participated, women accounted for only about 7 percent of the participants in Togo, and 5 percent of participants in Burkina Faso.
Jacques Jonathan Nyemb, a lawyer and policy advisor currently at the Harvard Kennedy School, suggested the most vital structural concern for entrepreneurs in Africa today was building the kinds of connected resources, linking human and financial capital, that help start-ups get off the ground in the U.S.
“People have a lot of ideas, but the most difficult thing is to move on a project,” Nyemb said. “I think it’s all about creating the ecosystem and trying to connect [people and resources] together.”
To that end, Munis added, “Building relationships is key. Within the Nigerian culture, they want to know you, so they can trust you. It’s part of doing business.”
“The youngest continent”
During a question-and-answer session at the end of the forum, audience members suggested that corruption and nondemocratic governments put a serious damper on Africa’s business climate. The panelists, though, contended that it is hard to generalize about such matters on a continent-wide basis.
“Corruption is a world-wide issue,” said Nyemb, who has worked on drafting laws and creating enforcement mechanisms for some African countries. “What is really important is training — training of magistrates, authorities, … [to] try to see how they can be the guardians of the rules.”
The upside of doing business in Africa now, as multiple panelists pointed out, is that it is a region with growth potential. While Nigeria has long been an oil-exporting powerhouse, Munis asserted that the current moment “is a great opportunity for us to get involved in sectors that have been neglected because of oil … now is the time.”
And Grunitzky, for his part, observed, “The single biggest attraction is demographic. … Africa is the youngest continent [by population age]. My biggest hope is the youth of Africa. I think they are going to create some incredible things.” | | 1:59p |
Uncovering the secrets of elastin’s flexibility Elastin is a crucial building block in our bodies. Its flexibility allows skin to stretch and twist, blood vessels to expand and relax with every heartbeat, and lungs to swell and contract with each breath. But exactly how this protein-based tissue assembles itself to achieve this flexibility remained an unsolved question — until now.
This material has a remarkable combination of flexibility and durability: Elastin is one of the body’s most long-lasting component proteins, with an average survival time comparable to a human lifespan. During that time, the elastin in a blood vessel, for example, will have gone through an estimated 2 billion cycles of pulsation.
A team of researchers at MIT, in Australia, and in the U.K. has carried out an analysis that reveals the details of a hierarchical structure of scissor-shaped molecules that gives elastin its remarkable properties. The findings were published this week in the journal Science Advances, in a paper by postdoc Giselle Yeo and professor Anthony Weiss of the University of Sydney, Australia; MIT graduate student Anna Tarakanova and McAfee Professor of Engineering Markus Buehler; and two others.
Elastin tissues are made up of molecules of a protein called tropoelastin, which are strung together in a chain-like structure, and which Weiss and his team have been studying in the lab for many years. In this work, they collaborated with Buehler and Tarakanova at MIT, who have specialized in determining the molecular structure of biological materials through highly detailed atomic-scale modeling. Combining the computational and laboratory approaches provided insights that neither method could have yielded alone, team members say.
While the study of elastin has been going on for a long time, Weiss says “this particular paper is exciting for us on three levels.” First, thanks to synchrotron imaging done by team member Clair Baldock at the University of Manchester in the U.K., the research revealed the shape and structure of the basic tropoelastin molecules. But these were snapshots — still images that could not illuminate the complex dynamics of the material as it forms large structures that can stretch and rebound. Those dynamic effects were revealed through the combination of computer modeling and laboratory work. “It’s really by combining forces with these three groups” that the details were pieced together, Weiss says.
Tarakanova explains that in Buehler’s lab, “we use modeling to study materials at different length scales, and for elastin, that is very useful, because we can study details at the submolecular scale and build up to the scale of a single molecule.” By examining the relationship of structure across these different scales, “we could predict the dynamics of the molecule.”
The dynamics turned out to be complex and surprising, Weiss says. “It’s almost like a dance the molecule does, with a scissor twist, like a ballerina,” with legs opening and closing repeatedly. Then, the scissor-like appendages of one molecule naturally lock onto the narrow end of another molecule, like one ballerina riding piggyback on top of the next. This process continues, building up long, chain-like structures.
These long chains weave together to produce the flexible tissues that our lives depend on — including skin, lungs, and blood vessels. These structures “assemble very rapidly,” Weiss says, and this new research “helps us understand this assembly process.”
A key part of the puzzle was the flexibility of the molecule itself, which the team found was controlled by the structure of key regions and the overall shape of the protein. The material has a combination of regions that are highly ordered and regions that are disordered. The disordered regions help to provide flexibility, while the ordered regions confer longevity.
The team tested the way this flexibility comes about by genetically modifying the protein and comparing the characteristics of the modified and natural versions. They revived a short segment of the elastin gene that has become dormant in humans, which changes part of the protein’s configuration. They found that even though the changes were minor and only affected one part of the structure, the results were dramatic. The modified version had a stiff region that altered the molecule’s movements and weakened it. This helped to confirm that certain specific parts of the molecule, including one with a helical structure, were essential contributors to the material’s natural flexibility.
That insight in itself could prove useful medically, the team says, as it could explain why blood vessels become weakened in people with certain disease conditions, perhaps as a result of a mutation in that gene.
While the findings specifically relate to one particular protein and the tissues it forms, the team says the research may help in understanding a variety of other flexible biological tissues and how they work. “The integration of experiment and modeling in identifying how the molecular structure endows materials with exceptional durability and elasticity, and studying how these materials fail under extreme conditions yields important insights for the design of new materials that replace those in our body, or for materials that we can use in engineering applications in which durable materials are critical,” says Buehler, who is head of the MIT Department of Civil and Environmental Engineering.
“We are excited about the new opportunities that arise from this collaboration and the potential for future work,” Buehler says, “because designing materials that last for many decades without breaking down is a major engineering challenge that nature has beautifully accomplished, and on which we hope to build.”
“This is fascinating work,” says Chwee Tak Lim, professor of biomedical engineering at the National University of Singapore, who was not involved in this research. Lim says “I believe this work is significant in that it not only enables us to better understand the requisite conditions for the formation of ‘healthy’ elastins, whether in our body or in producing them for biomaterial applications, but also provides insights into certain tissue dysfunctions arising from elastin mutations.”
The research team, which also included Steven Wise of the Heart Research Institute in Sydney, was supported, in part, by grants from the Australian Research Council; the National Institutes of Health; the Wellcome Trust; the Biotechnology and Biological Sciences Research Council, UK; and the U.S. Office of Naval Research. |
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