Thursday, May 7, 2009
The use of renewable energy sources to replace coal, oil and natural gas is one of the primary methods for achieving a more sustainable future. Renewable energy sources include biofuels, solar energy, wind energy, and geothermal energy. Below is a discussion of each of these sources as community or regional energy sources. The use of these renewable energy sources on individual buildings is later in this blog under the section dealing with sustainable building design.
Monday, May 4, 2009
Biofuels refers to renewable plant matter that is used as a replacement for coal, oil or natural gas to produce energy. This can either be through direct combustion or through the conversion of the plant matter to synthetic fuels such as biodiesel. Biofuels become even more efficient when the plant is harvested for food and only the waste materials from the plant is converted to energy.
Geothermal energy production is a renewable energy source that extracts the heat from the earth's interior. The cost of geothermal energy production is greatly dependent upon how close to the earth's surface are located geothermal vents. In locations such as Iceland and Hawaii where there exists active volcanic activity, geothermal energy is an attractive source of renewable energy. Pictured above is a geothermal power plant built in Iceland.
Solar power, or energy from the sun, is by the earth's most abundant renewable energy source. Unfortunately, while having great potential, last year solar energy production accounted for only 0.02 percent of the world's energy consumption. With concern about global warming, however, governments are providing financial incentives for solar energy production, which helps to create demand and bring down the cost of solar energy technologies. Also, new approaches for solar energy production are being developed, such as that illustrated above where solar rays are concentrated in a single collecting mirror that allows for the building of large solar energy power plants. Examples of such solar energy power plants include the 46 MW Moura solar power plant in Portugal, the 40 MW Waldpolenz solar power plant in Germany, and the 11 MW PS10 solar power plant (illustrated above) in Seville, Spain.
Wind energy is another form of renewable energy. Modern wind turbines have become very efficient at transferring the energy of the wind to electricity. To demonstrate the potential of wind energy, electrical generation from wind turbines grew by 28.8 percent world-wide last year. Two innovative new uses of wind energy are: (1) specially designed new wind turbines that can be mounted on the roofs of urban buildings; and (2) the idea of creating a smart grid where wind energy can be exported from areas of high winds to urban areas needing the energy. Another innovative proposal is to build a grid of wind turbines in the upper midwest of the U.S. to provide cheap energy to extract natural gas from lands containing oil shale.
The heating, cooling and lighting of our buildings accounts for 48 percent of all U.S. energy consumption. As such, building energy usage is the greatest contributor to green house gases and global warming. This will only increase as the world becomes more urbanized and the built environment represents a greater and greater portion of our environment. Stormwater runoff from buildings is also one of the greatest non-point sources of water pollution, while the manufacturer of synthetic materials used in the construction of buildings leads to hazardous waste and an increasing number of "sick" buildings. Following is a discussion of methods of constructing "green" buildings so as to promote a more sustainable environment.
Green roofs are one of the most visible ways to build more sustainable, "green" buildings. A study conducted for Toronto, Canada estimated that the installation of green roofs on buildings could: reduce the heat island effect of urban areas by 1 to 2 degrees C, reduce smog alerts in cities by 5 to 10 percent, absorb CO2 emissions from automobiles and thus reduce green house gases, reduce the energy needs of buildings for heating and air conditioning, filter storm run-off and thus reduce water pollution, and expand recreational and open space in urban areas by creating roof-top gardens.
Solar photovoltaic panels are used to convert the sun's energy into electricity. A converter is used to convert the electricity from DC to AC electricity. Any excess electricity can be stored in batteries or exported to the electrical grid and sold to the local electrical utility.
Passive solar is any means to use the heat from the sun to provide for the heating or energy needs of a building without any means of mechanical assistance. The easiest method of passive solar involves the proper siting of a building to take advantage of the sun when it is at a low horizon or angle, but to provide shading when the sun is at its highest during the hottest part of the day. Another means of passive solar design is to build the floor of a building with some type of thermal mass such as concrete that absorbs the heat - and releases the heat at night when it is cooler.
Previously, wind turbines as an energy source were typically not located on building or within urban areas. With the concern about green energy and global warming, however, new technologies have recently been developed to allow wind turbines to be built on top of buildings -- and be able to deal with the shifting wind directions typical of urban areas. As such, wind turbines are increasingly a part of sustainable green buildings.
Traditional fiberglass insulation is harmful to the environment both in its manufacturer and in its use. A more eco-friendly type of insulation is recycled cellulose insulation. The cellulose can come from such diverse sources as recycled newspapers or recycled blue jeans.
Geothermal heating and cooling involves the use of ground source heat pumps to take advantage of the fairly constant ground temperature to reduce the cost of normal heat pumps to provide for heating and cooling. Wells are dug to a depth of typically 200 feet to obtain a source of air that is approximately 55 degrees year around. This reduces the need for cooling the outside air for air conditioning in the summer and for heating the outside air in the winter, and thus provides for a more efficient form of heating and air conditioning of buildings.
Another method of sustainable green building design is to incorporate means of natural ventilation and lighting into a building, and thus reduce the need for energy use. Innovative new methods of accomplishing this are solar tubes mounted on the roof of buildings that bring concentrated sunlight into buildings and often replace the need for daylight lighting within the building. Also, buildings are increasingly being built with vents on the roof that can be opened to suck the hot air out of buildings and with windows that open that can draw fresh air into buildings.
One example of a proposed sustainable "green" building is the Ecolaboratory building to be built on the 7,200 square foot P-patch in the Belltown neighborhood of downtown Seattle. Conceived by Weber Thompson, it is proposed that the main living units of the building be constructed of recycled shipping containers. All water, including black and gray water, is to be recycled for the use of residents and landscaping water needs. Residents will be able to individually control the amount of their natural ventilation by the design of what are referred to as "earth tubes." Solar hot waters panels will provide for the heating of hot water. Also providing energy for the building will be photovoltaic solar panels, biomass conversion, and even hydrogen fuel cells - to generate electricity.
To demonstrate how a sustainable home can be constructed, Duke University in conjunction with Home Depot has built a sustainable "smart home" demonstration. It has received a LEED (Leadership in Energy and Environmental Design) platinum rating, the highest level rating. It includes solar water panels for hot water heating, 18 photovoltaic solar panels that generate 3 kW of electricity, a vegetated green roof planted with sedums that are drought tolerant and capture and filter rainwater while providing roof insulation, rainwater collection for irrigation of the grass of the site, Energy Star appliances, and recycling of construction waste materials.
An example of a sustainable green building that takes advantage of natural ventilation is the Environmental Nature Center in Orange County, California.
Sunday, May 3, 2009
The proposed Independence Station building claims that, when constructed, it will be the highest rated Platinum LEED (Leadership in Energy and Environmental Design) building in the world. It will include almost all of the various approaches to green building design (green roof, photovoltaic solar panels to generate electricity, passive solar hot water heating, geothermal heating and cooling, rainwater harvesting, etc.)
The Clinton Presidential Library in Little Rock, Arkansas is the first presidential library to be designed green. When it opened, it received a silver LEED (Leadership in Energy and Environmental Design) award, but has since been upgraded to the highest award level -- i.e. a platinum award. It has a green roof with approximately 90 different types of plants, solar panels, and includes a wetlands next to it that is protected as part of the library.
One of the best examples of a building design with a green roof is the "living roof" of the newly constructed California Academy of Science in San Francisco.
The BedZED Eco-Village located in Wallington, South London, England is intended to be a zero-energy, carbon neutral community development. Opened since 2002, it is designed to house 100 families, community facilities, and office space for 100 workers. Developed by Peabody Trust in conjunction with Bioregional Development Corporation and designed by architect Bill Dunster, its homes are designed to use only 10 percent of the energy of a typical home.
The Brighton Earthship is an experimental sustainable building near Stamner Park, Brighton, East Sussex, England. Its walls are made from recycled tires and it is built semi-underground to use the insulation properties of the earth itself. It includes a windmill and passive and active solar heating, as well as geothermal heating and cooling.
Tuesday, April 21, 2009
Sustainable urban and regional planning is the philosophy of designing and planning the human-built environment to comply with principles of economic, social and ecological sustainability. Originally first articulated as a criterion for urban design and planning back in the 1970's by Richard Hopper (then Hawaii's State Environmental Planning Coordinator) both in an article published in the magazine of the American Planning Association and as part of an effort he led to develop a "Quality Growth Policy for the State of Hawaii," sustainability is no longer a concept limited to the field of biology. Instead, as Hopper articulated back in the 1970's all natural and man-made systems have an inherent carrying-capacity that can either be: (1) used as a limit for growth; (2) ignored and exceeded with the consequence of thus degrading the system; or (3) expanded through new technologies and method of design and planning. As such, applying the concepts of sustainability and carrying-capacity to the design of our man-made built environment helps to protect the quality of both our man-made and natural environment.
One of the first principles of sustainable design and urban and regional land use and transportation planning is to recognize that we are all connected, and what one of us does affects us all. As such, sustainable design and urban planning is about creating sustainable "communities." This means that we need to be concerned not only with the direct and obvious negative environmental impacts that can be traced to our individual actions, but that we also need to address the collective and cumulative impacts of our societal activities. That is where urban and regional design and planning comes in. Urban and regional design and planning is how we as a community or society can work cooperatively to build sustainable communities. Urban and regional design and planning consists of three components: (1) research to identify problems; (2) brain-storming through design charettes and other means to develop alternatives; and (3) public participation to reach consensus on proposed means of implementation. Urban and regional design and planning, however, does not replace the political process in making the ultimate decision on implementation actions such as revised zoning, public infrastructure funding, etc. What urban and regional design and planning does is to help promote informed decision-making and a long-range vision to guide development. In this context, what sustainable design and urban planning does is to include sustainability is a criterion to help guide development decisions.
Sustainable design and urban and regional land use and transportation planning is guided by several principles borrowed from biology or the natural environment. These include the concepts of: (1) connectedness; (2) renewability; (3) efficiency; (4) minimization of externalities or negative impacts; and (5) carrying-capacity. Urban planners and designers that are interested in achieving sustainable development and communities use a variety of new urban design and planning principles and techniques to help achieve these concepts or goals of sustainability. These include smart growth strategies, new urbanism designs, sustainable urban infrastructure, and new strategies to bring the natural environment back into our urban man-made environment. Following is a discussion of some of these techniques of sustainable land-use and transportation planning and management.
MASS TRANSIT -- Next to the energy used to heat and cool buildings, the greatest amount of energy we used is in transportation. As such, any sustainable design and planning of our urban communities needs to incorporate the use of mass transit and other innovative forms of energy efficient transportation as they are invented. In this regard, we need to be careful that our zoning and building codes do not lock us into outdated technology. As an example, today buildings and mass transit are designed separately. As a consequence, it is often a long walk outdoors to access mass transit, thus discouraging the use of mass transit. What is even worse is that too often mass transit stations are only accessed by driving to them by automobile and parking. A better design would be to allow residential and commercial use all within walking distance of transit stations, and to construct major civic and other buildings where mass transit is immediately adjacent or connected to the buildings. Also, if we want to encourage mass transit, we need to find better ways to accommodate the needs of the disabled so that mass transit is available to all. Finally, in today's "information age" we need to find a better way to use information and smart technologies to better manage traffic flow so as to help the wasted energy of individuals sitting in congestion.
"NEW URBANISM" AND "SMART GROWTH" LAND DEVELOPMENT -- In the 1920's, landscape architect John Nolen designed a new suburb on the outskirts of Cincinnati, Ohio. This new suburb was named Mariemont and was meant to be a "National Examplar" of how suburbs should be designed. It was connected to Cincinnati by streetcar and by Route 50 which ran through its center. As such, it was the first transit-oriented suburb. It also was designed with all the schools and town center to be within a five or ten minute walk from all parts of the community. As such, it was designed to be promote walking and bicycling. To make the community even more pedestrian-friendly, numerous small to medium sized parks were scattered evenly throughout the community, park benches were built on street corners, streets were designed to be narrower than the typical modern suburban street to slow traffic, and large shade trees were planted between the sidewalks and streets to provide shade for pedestrians. Also, the garages of homes were set even with or behind the homes acccessed by alleyways. Through his planning of Mariemont and other subsequent communities and cities, John Nolen is credited with being the "father of modern urban planning." Ironically, the demand for housing after World War II caused the nation to abandon the planning model of John Nolen and instead to develop sprawling residential only suburbs in the model of Levittown, New York. These newer suburbs were designed for the automobile as opposed to pedestrians or mass-transit. They also abandoned the concept of integrated mixed-use as John Nolen had designed for his Mariemont community. Today, however, the 1950's style of suburban sprawl after the model of Levittown is understood to be energy efficent, wasteful of land, a contributor to air pollution and global warming, destructive of the natural environment, and destructive of of the sense of community. For this reason, urban planners and designers are increasingly turning back to the model of Mariemont as designed by John Nolen. When employed in for a suburban development, this model is typically referred to as "New Urbanism." When employed in the design of a closer-in and more dense semi-urban development, this model is typically referred to as "Smart Growth." In fact, both emphasis the same principles emphasized by John Nolen -- i.e. pedestrian oriented, transit-based, mixed-use development, with the purpose of both being to make urban and suburban development more sustainable and compatible with both the human and natural environment (as opposed to emphasizing the automobile). These two models for land development and zoning have become the primary methods of urban planners to make urban land use more sustainable. One of the first examples of "New Urbanism" is the community of Kentlands in Gaithersburg, Maryland -- while two of the more recent and best examples are Celebration in Orlando, Florida and the King Farm in Rockville, Maryland (with the latter being initially designed by Richard Hopper, who is referred to above as having initiated the concept of sustainable design in urban planning and development back in the 1970's and who then went on to also become one of the pioneers in promoting recycling and resource recovery). With respect to the concept of Smart Growth, perhaps the best known example of efforts at "Smart Growth" is Montgomery County, Maryland (with the King Farm referred to above being part of Montgomery County, Maryland's efforts to promote "Smart Growth").
Above is a site plan for the "New Urbanism" community of the King Farm in Rockville, Maryland. The gray colored line running through its middle from left to right is a road where the center right-of-way is reserved for light rail, to connect the subway to the right where the road runs also runs into Rockville Pike. Until the light-rail is built, the center right of way is being used for a special bus to take residents to the subway, which then goes to downtown Washington, D.C. The King Farm is a mixed-use development with a town center and schools that consists of 3,200 residential units and 3.2 million square feet of office. It has received numerous national awards for its "New Urbanism" design.
Monday, April 20, 2009
PRESERVATION OF URBAN "NATURAL ENVIRONENT" -- Until recently, the approach to urban planning and development was to pave over natural environments and to replace streams with concrete pipes. This increased stormwater runoff and pollutants and sedimentation that ran into our rivers, bays and estuaries. With sustainable urban design and planning, however, the new approach is to preserve and protect as much of the natural environment as possible in our urban areas to filter stormwater runoff, preserve wildlife habitat, and to reduce the "heat island effect" of our urban areas. In summary, the new sustainable approach to urban planning and design is to preserve the "green" in our urban man-made environments.
THINK GLOBALLY, ACT LOCALLY -- Ultimately, the most important solution to sustainable design and urban and regional planning is yourself. There is not one solution to sustainability that is the best fit for all communities. Each community has its own unique needs and potentials. The key is citizen activism and commitment to the principal of making their own community sustainable. Out of such citizen activisim around the world are coming the most wonderful solutions. An example is the Danish island of Samso. Covering an area of 46 square miles, or approximately the size of the island of Nantucket, the citizens of Samso decided that they were going to make themselves totally energy self-sufficient. By constructing wind turbines, solar panels, and burning their biomass to produce energy, not only has Samso become totally energy self-sufficient -- but it now exports energy to the Danish mainland! Following the Samso example, the entire country of Denmark has now committed to energy self-sufficiency and produces 20 percent of its total energy needs from wind turbines, and has become the world's leading manufacturer and supplier of wind turbines. This compares to the United States where only 1 percent of our energy comes from wind turbines. Isn't ironic that a country has vast as the United States with its huge potential for wind turbines has to buy wind turbines from Denmark to install in Texas, California and elsewhere throughout the country. Denmark and the people of the island of Samso have learnt the basic lesson that not only does sustainability make environmental sense, but it also makes economic sense.
PURCHASE OF DEVELOPMENT RIGHTS -- Another example of citizen activisim to create a more sustainable environment is the Purchase of Development Rights Program (PDR Program) created by Loudoun County, Virginia. Loudoun County is one of the most beautiful areas in the country with horse farms, vineyards, the Blue Ridge Mountains, and bordered by the Shenandoah and Potomac rivers. Unfortunately, it is a suburb of Washington, D.C. and thus is steadily being consumed by urban sprawl. To help protect the open space of the western part of Loudoun County, the Piedmont Environmental County and other citizen organizations and individuals banned together to convince the county to enact its Purchase of Development Rights Program. This was a program to purchase the development rights on agriculture and other undeveloped pieces of land so as to preserve the open space in western Loudoun. This was cheaper than actually purchasing the land, and allowed landowners to become the stewards to protect the land. The program was funded with allocations from the county's tourist occupancy tax imposed on hotel rooms (with the hotels in Loudoun County being primarily located near Washington's Dulles airport). At the same time, the program helped to promote tourism as the beautiful horse farms, vineyards and civil war sites in Loudoun county make it one of the most popular tourist destinations in the Washington, D.C. region. One of the individuals that helped to push for the creation of the PDR program and who then served on the PDR Board was Richard Hopper, who previously in his role as Hawaii's State Environmental Planning Coordinator had developed a Quality Growth Policy for Hawaii and who developed the initial plan for the "New Urbanism" community of King Farm across the Potomac River from Loudoun County, Virginia in neighboring Montgomery County, Maryland.
After being devasted by a tornado, the town of Greensburg, Kansas decided to rebuild itself with all of its public buildings being LEED (Leadership in Energy and Environmental Design) Platinum rated. It's first public building designed to this center, i.e. the Greensburg Arts Center, is the first platinum rated green building in Kansas. Designed by the non-profit Studio 804 of the University of Kansas, it is built with special tempered glass that blocks UV rays, 4 inch concrete floors that help retain the heat in the winter, skylights to allow in natural daylight, a green roof planted with the succulent plant sedum to absorb UV rays and reduce the need for air-conditioning in the summer (while the soil medium helps insulate and reduce the need for heating in the winter), cellulose insulation made by recycled newspapers, and both 3 Kestrel wind turbines that produce 600 watts of electricity and photovoltaic solar panels on the roof that all are used to provide electricity to the building. A converter in the basement converts the DC electricity to AC electricity, and what electricity that is not used is either stored in 12 batteries or is sold as excess to the city. The building also has 3 geothermal heating and cooling wells that draw 55 degree temperature air from 200 feet deep that makes the heat pumps of the building more efficient in both the winter and summer. Finally, rainwater from the building is collected in a 1500 gallon cistern and is used to water the natural buffalo grass lawn. The City of Greensburg has been featured in a series shown on the television station Planet Green to demonstrate what has been accomplished by one community's commitment to a more sustainable future.
Denison University in the town of Granville near Columbus, Ohio - famous for being one of the best small liberal arts colleges in the U.S. - has committed itself to be a sustainable university community. Above is a picture of the green renovations being made to Cleveland Hall. Once completed, Cleveland Hall will be an LEED rated building. Denison has also installed solar panels on its library, instituted a university recycling program, instituted a university composting program, established a program of environmental studies, and has research grants available to undergraduate students who want to pursue research projects in sustainability.
IN SUMMARY, SUSTAINABLE DESIGN AND URBAN PLANNING IS NOT ONLY GOOD FOR THE ENVIRONMENT, BUT ALSO HAS A POSTIVE ECONOMIC COST-BENEFIT -- Non-sustainable development assumes that it is too expensive to factor in the impacts of development on the natural environment and the livability of the overall community. Experience in the development of new urbanism communities like Mariemont, Ohio, planned communities such as Reston, Virginia and the re-development of downtowns such as Portland, Oregon, however, demonstrate that property values increase when the natural environment and the quality of life of a community are protected. People and businesses eventually flee unsustainable communities for a better life elsewhere. Sustainable communities, however, retain their populations from one generation to another and from one economic period to another. Also, experience shows that ultimately unsustainable development costs more. Unsustainable buildings become outdated as energy costs rise while residents flee cities that have allowed sprawl and pollution overtake the human and natural environment. And eventually air pollution regulations might limit new development in regions that have allowed themselves to be dominated by sprawl while business and residents move to the suburbs or to other cities that do not have the costa and problems of urban regions that were not designed to be sustainable. Sustainable design and urban and regional planning is not only earth-friendly and helps to address global problems such as global warming and climate change, but it makes economic and social sense as well.