Yes, we all want to help save the planet, but a little more immediate pay-off would be nice, too. The ideas here are not just about what you give up, they’re about what you get – more comfort, more light, cleaner air, less expense, for starters, and as you’ll see, the more you do, the more benefits you’ll find.
“We’ve come a long way from old building stock when energy didn’t matter. Now we have to make another leap.” (Deane Evans, FAIA, New Jersey Institute of Technology, featured in the Green Builders film)
Here are some of the basic strategies in renewable energy technologies. The Green Builders production team, based in New Jersey, didn’t have to travel far to find examples of renewable energy projects that were already up and running. You’ll find these people and places when you watch the film.
1. Sun. Enough sunlight falls on the earth in one minute to power the world’s entire current energy needs for a year! The problem, of course, has been harnessing it cost-effectively, but the costs are coming down (just as the cost of “conventional” energy goes sky high) and the technology is experiencing an innovation boom. The basic strategies are active solar systems, as in the panels on roofs that help heat water and spaces; photovoltaic systems, which convert sunlight to electricity, and can be mounted on roofs (often in thin tiles that look like ordinary – lazy and non-productive --roof tiles), in large arrays, or on the ground; and passive solar, where the sun is utilized in non-mechanical ways, by the very design and structure of the building, as in large window areas that collect light . But there are countless combinations and configurations of solar technologies available, from small scale to extremely large.
According to Thomas Leyden of Sunpower Corporation, every state in the U.S. has enough energy to take advantage of solar, but three factors are key: 1) how much energy is available in the area from sun, 2) what the cost of the energy is that the solar is displacing, and 3) what incentives are available locally. New Jersey happens to have all three of these factors in its favor, and is in fact, the second largest solar market in the country, second only to California. The National Renewable Energy Laboratory is a good place to start in all matters renewable.
2. Wind. If the question is where are we going to get free energy more plentiful than oil, then the answer is blowing at the Atlantic County Utilities Authority in Atlantic County, New Jersey. The wastewater management plant there is one of the largest users of electricity in the region, operating 24/7 year round. Now with their wind turbines, they have created a wind farm where they can harvest all the energy they consume and sell the excess back into the grid.
It has been estimated that if the U.S. constructed enough wind farms to fully tap into wind resources, especially in very windy areas like the Great Plains, the turbines could generate as much as 11 trillion kilowatt-hours of electricity, or nearly three times the total amount produced from all energy sources in the nation last year.
3. Wind plus sun. The Atlantic County site also makes use of two empty, otherwise idle rooftops on the site, with solar arrays over the employee parking lot, and ground mounted photovoltaic panels elsewhere on the property. Almost 70 percent of their total energy consumption comes from renewable energy. Many experts think the future of large scale renewable energy production will come from a combination of solar cells and wind turbines.
4. Energy inside the earth. Geothermal energy, or energy from the earth, covers a wide spectrum of technologies, from small heat pumps suitable for use in a single house, to very large power plants tapping deep below the earth’s crust. In the earth tubes at Aerzen USA, a manufacturing facility in Pennsylvania, air is drawn from outside into pipes buried deeply underground. The natural coolness of the earth tempers the air and is drawn up into the manufacturing plant to keep occupants cool. Earth one, carbon zero.
The geothermal system at The Richard Stockton Collegein Pomona, New Jersey, injects heat deep into the ground during summer, spring and fall, through 400 boreholes 425 feet below a parking lot, and stores the heat (they call it the equivalent of a giant car radiator!) to be used during the winter. (It can work the other way, too, storing coolness. See “Aquifers” next.) At least 98 percent of the heat that’s injected in the summer is available six months later.
5. Aquifers. Also at The Richard Stockton College, deep aquifers also act as cooling storage. Water is cooled and then replaced into the same aquifer, about 1000 feet away, resulting in a huge, almost circular cold store, 100 feet deep and 400 feet in radius. According to Dr. Lynn Stiles, Professor of Physics and Coordinator of Energy Studies, the system is approximately 3-6 times that of using a geothermal system, and a geothermal system is already two times more efficient than air conditioning. Geothermal heat pumps for small buildings can also take advantage of the fact that the earth is a constant 55 degrees temperature, so they can help moderate temperatures year round, delivering heat in winter and coolness in summer.
6. Co-generation. In the simplest terms, co-generation plants generate both electricity and heat, which is then captured for use instead of being lost to the environment. At Princeton University, the co-generation power plant uses an FA-18 engine designed for a Stealth fighter to make electricity for the entire campus, and the hot exhaust from the engine heats water to provide steam. The plant also incorporates large electric chillers to buy electricity at night, when it is less expensive, to chill a 2 ½ million gallon tank of water, which is used to deliver air conditioning.
7. Hydrogen. Often considered the Holy Grail of renewable energy. Theoretically, if we could learn to use hydrogen for fuel, we would have unlimited, perfectly clean energy (learn more about Hydrogen Basics). One way is to produce hydrogen from electrolysis, using electricity to split water into hydrogen and oxygen, using solar energy, for example, or other kinds of renewable energy. But doing it on a large scale, or producing cars that can run on hydrogen, still presents a formidable challenge. However, there is no question that it works. The question is “only” the cost. At the Hopewell Project in Hopewell, New Jersey, solar energy converts water into hydrogen and oxygen, and the hydrogen is then stored in tanks, forming a hydrogen fuel cell that is the equivalent of 60,000 batteries. The building also has a solar system and a geothermal heat pump. When additional energy is needed, for example during the winter when more heat is required, it is provided by the stored hydrogen, converted back into electricity (and water and heat).
8. Passive solar design and daylighting. Just orienting a building properly can change the energy efficiency of that building as much as 30 percent. Although many renewable energy options are technological in nature, the fundamental first requirement is design, which uses the most important resource (and often the one in shortest supply): thought. For example, a building that is oriented to take advantage of the sun’s heat in winter but to avoid glare and heat gain from western exposures will not require as much energy of any kind, either conventional or renewable. A building that has ample, carefully designed window space will reduce the need for electric lighting, but give occupants comfortable, glare free light. Studies show that patients heal faster, students score higher, and workers are more productive with large amounts of natural light. Some introductions to passive solar design in houses are at Sustainable Sources and Sustainable Buildings Industry Council.
9. Infinite combinations. In the Meadowlands in northern New Jersey, acres of roof space on warehouses are perfect candidates for solar arrays, and the municipality encourages developers to build green through incentive programs.Along the Jersey Shore in Belmar, houses incorporate energy conservation measures, proper orientation and design, solar electricity and solar water heating, and the municipality focuses on recycling entire old houses for energy savings and smart growth. Most energy conserving options are even more effective when combined. As more and more smart people get involved with green design and green thinking, the options are proliferating, and successful sustainability will rely on new combinations.