3 Sustainability Case Studies

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1 3 Sustainability Case Studies COMMUNITIES AROUND THE world face a variety of sustainability challenges. Even though the challenges differ from one community to the next, there is often one similarity: many sustainability issues are a result of overuse of the earth s resources. In this activity, you will read about two communities that have taken steps toward more sustainable use of resources. Challenge What steps have communities taken to live in ways that are more sustainable? MATERIALS FOR EACH STUDENT Student Sheet 3.1, Summary Sheet: Sustainability Case Studies Student Sheet 3.2, Three-Level Reading Guide: Sustainability Case Studies Procedure 1. As you complete the reading, fill out Student Sheet 3.1, Summary Sheet: Sustainability Case Studies. 2. When you have finished the reading, complete Student Sheet 3.2, Three-Level Reading Guide: Sustainability Case Studies. Reading EVERYDAY DECISIONS Every day people make personal decisions about transportation, food, and use of water and other resources. On an individual level, these decisions seem to have little impact on the world. However, when the effects are multiplied by large numbers of people, the results are significant. The sum of many individuals actions can increase or decrease the sustainability of the community. Here are the true stories of two places where the actions of individuals made a difference in the sustain ability issues facing their communities. BEDDINGTON ZERO FOSSIL ENERGY DEVELOPMENT, ENGLAND Beddington Zero Fossil Energy Development (BedZED) is one of a handful of developments, or ecovillages, in the world that were designed and built to encourage people to live using fewer resources. Completed in 2002 near London, 14

2 SUSTAINABILITY CASE STUDIES ACTIVITY 3 BedZED has 100 living and work spaces. A team of scientists, engineers, and architects designed the community, with help from the local government. One of the primary goals of BedZED was to reduce the amount of fossil fuels burned for energy. Our continued reliance on fossil fuels is releasing more and more carbon dioxide into earth s atmosphere. A growing body of evidence shows that, as a result, climates around the world are changing often in harmful ways. Developed countries, in particular, such as England and the United States, give off relatively high amounts of carbon dioxide emissions. To build BedZED the designers chose cost-effective materials that had a life cycle with a smaller ecological impact than standard products. The product life cycle describes the amounts of resources and energy it takes to make a product, the length of the product s usefulness to the consumer, and how the product is disposed of, recycled, or reclaimed when it is no longer needed. In general, a more sustainable product is made from relatively more reclaimed material and less raw material, and requires less energy to produce and transport it. BedZED is one of the world s best-known eco-villages. 15

3 SCIENCE & GLOBAL ISSUES/BIOLOGY SUSTAINABILITY The life cycle of this wood waste could be extended if it were recycled or repurposed instead of being placed in a landfill. For example, the life cycle of a wooden board includes the energy and resources used in cutting the tree, transporting it to the mill, cutting the board, shipping it to a distributor, and transporting it to the construction site. The life of the wooden board continues for however long it is part of the constructed house. The useful life of the board is likely to end when the house is torn down or remodeled. Since construction debris usually ends up in a landfill or is incinerated, more energy is consumed to transport the board to a landfill or incinerator, its final destination. The life of the board, however, goes on because there are both economic and environmental costs to maintain it in the landfill or burn it in an incinerator. Sometimes a board does not go to the landfill or incinerator but is, instead, reused or recycled. Then the materials would be put back into the cycle, whether to become part of another house or go into another product. In either event more energy and resources go into this next life. In this way, a product s life cycle is never really a closed loop. The term cycle can be misleading because the life cycle of a product does not necessarily mean the resources in the products are reclaimed and continually cycled through different states. PRODUCT LIFE CYCLE 16

4 SUSTAINABILITY CASE STUDIES ACTIVITY 3 As well as selecting materials that have a lighter ecological impact, BedZED s builders designed the complex so that residents would rely less on energy and water in their daily routines. For example, the apartments have energyefficient refrigerators, washers, dryers, and other appliances. Rooms and windows are placed to maximize the amount of sun to heat the house during the day. Water meters are installed at eye level in the kitchens, rather than being put outside of or under the homes, so that residents can monitor the amount of water they use. A community composting and recycling system begins with a built-in waste collection center in each kitchen. Recycling goes even further with a special office-paper recycling plan in which all used paper is recycled and returned to BedZED for reuse. One of BedZED s goals is to provide alternatives to private car travel. BedZED s electrical power was originally generated by solar panels and a biofuel power system. The biofuel power system generated energy by burning recycled garden waste instead of fossil fuels. The biofuel power system supplied electricity and heat to the community. Unfortunately, there were problems with the system. Residents had to use gas-powered water heaters, and a majority of their electricity came from the regional power plant. Since transportation contributes to carbon dixoide emissions, BedZED was designed to help its residents reduce trips outside the community. For example, there are on-site workspaces, exercise facilities, a community center, and a bicycle repair shop. When residents travel, they do so by taking advantage of BedZED s carsharing program, electric cars, nearby bus and subway lines, and bicycles. Although BedZED residents travel less frequently by car, they tend to fly more often. As a result, they have a slightly higher than average overall transportation impact. Having so many resources within BedZED also has the effect of maintaining a strong social community. About 84% of the residents feel that the community is an improvement on their previous neighborhood. On average, they know more than twice as many neighbors as those in the surrounding area. Since the apartments are desirable places to live in, the sale price of a BedZED apartment is higher than similar nearby apartments. After the project was completed, data from water and energy indicators were collected. In comparison to the average Londoner, BedZED residents use less energy in the home, consume less water, and drive fewer miles. 17

5 SCIENCE & GLOBAL ISSUES/BIOLOGY SUSTAINABILITY Some of the indicators, measured five years after project completion, are shown in the table below. BedZED Data INDICATOR Energy consumption AVERAGE IN ENGLAND BEDZED GOAL 2007 BEDZED AVERAGE Electricity consumption at home (kwh/person/day) (33% reduction) 3.4 Heat consumption, space and water heating (kwh/person/day) (90% reduction) 5.2 Total energy consumption (kwh/person/day) (80% reduction) 8.6 Water consumption (liters/person/day) (33% reduction) recycled or rain water Carbon emissions (kg CO 2 /person/day) 25 0 (100% reduction) 1.4 Personal fossil fuel car mileage (km/person/year) 6,344 3,172.0 (50% reduction) 2,318 SOURCE: BioRegional, 2009 While BedZED has met its goal of reducing residential energy consumption, it has experienced its share of challenges. Energy consumption has not been reduced as much as planned. The cost to build BedZED ran higher than expected. Critics claim BedZED is a failure because it relies on some fossil fuel for energy. Supporters say BedZED is still successful because it took fewer resources to build than other living complexes, and residents use less water and energy than they would in traditional homes. The photovoltaic solar panels at BedZED provide electricity and help shade the house in warm weather. 18

6 SUSTAINABILITY CASE STUDIES ACTIVITY 3 DAREWADI WATERSHED RESTORATION PROJECT, INDIA Darewadi is a rural village of about 2,500 people located in India, east of the city of Mumbai. The residents of Darewadi are primarily farmers and herders, who make their living raising crops and animals to sell in nearby communities. Although the region receives little rainfall each year, the local resources had supported the village population for many years. However, by the early 1980s, overfarming, overgrazing, and population growth caused changes to the local ecosystem. As a result, less arable land was available because farming had exhausted the soil. To create more farmland the residents began clear-cutting the natural landscape, removing trees and shrubs that held water in the ground. This dried out the soil even further. The villagers faced a crisis in the mid- 1990s when there was no longer enough water and arable land to support the residents of the village. Not wanting to abandon their homes, the residents of Darewadi had to find ways to support themselves. Many traveled for months on end to neighboring villages and cities to find work. For those who stayed, water was brought in by truck during the extremely dry summer months. The Darewadi villagers everyday activities, over the years, had caused their land to degrade. Land degradation is the decline in the overall quality of soil, water, or vegetation caused by human activities or natural events. Land degradation caused by human activities is not unique to Darewadi it occurs all over the world. In 1996, a nonprofit group together with the Indian and German governments started the Indo-German Watershed Development Project. The project depended on the knowledge of scientists that specialized in agriculture, forestry, and the movement of water. The goal of the project was to restore the Darewadi watershed and land to a condition that could once again support the population. First, the project convinced Darewadi residents to change their approach to the land and trained them in skills that would restore the ecosystem. Working with the leadership in the village, specialists taught sustainable farming practices, and residents learned how to build trenches and dams to harvest rainwater and underground water. The villagers made a difficult choice when they agreed to stop raising and herding grazing animals. This ban protected the land from further harm and gave it time to recover. To encourage regrowth, the villagers planted native trees and grasses, and prohibited the cutting of all trees and shrubs for five years. In addition, a community board made up of members from every social group 19

7 SCIENCE & GLOBAL ISSUES/BIOLOGY SUSTAINABILITY The Darewadi Watershed Restoration Project Data INDICATOR BEFORE PROJECT, 1996 AFTER PROJECT, 2001 JANUARY 2005 Months requiring delivery of drinking water by truck February to June none none Active wells (number) Livestock 1, ,007 Agricultural employment (months per year) Agricultural wage rate (rupees per day) Kitchen gardens Televisions Bicycles Waste land area (hectares) Cropped area (hectares) ,085 SOURCE: Watershed Organization Trust, 2005 was set up to oversee the project. Some indicator data for the project is shown on the next page. Within five years positive effects were seen in the Darewadi community. The volume of water in the watershed increased, and it was no longer necessary to truck in water. Grasses and trees grew back. Rather than relying on a single grain crop, millet, farmers grew a variety of new crops, including vegetables. More residents were able to stay and farm year-round in Darewadi. Villagers learned to maintain the local resources by using different methods of tending to the soil. SOLVING SUSTAINABILITY CHALLENGES These two case studies show the changes communities can make by applying science and technology to improve their lives and maintain natural resources for future generations. In both BedZED and Darewadi, scientific knowledge contributed to improving the economic, environmental, and social lives of the communities. These examples show how science and technology can play an important part in solving sustainability issues. Analysis 1. For each of the two case studies explain: a. What kind of indicators were monitored economic, environmental, and/or social? b. What do the indicators show about the effects of the changes that were made? 2. What specific science- and technology-related changes did the communities make that lowered their 20

8 SUSTAINABILITY CASE STUDIES ACTIVITY 3 a. energy use? b. water use? 3. Give an example of a potentially unsustainable practice involving natural resources in your community. a. Use indicator data to show how it is not sustainable. b. Propose alternatives to this activity that might be more sustainable. Explain why your choice(s) are more sustainable. c. What are the trade-offs you would have to consider when deciding whether or not to adopt the alternatives? d. What indicators would you use to determine if the alternative was sustainable? KEY VOCABULARY indicator land degradation product life cycle sustainability 21