“Someday this food will be in all markets!”
Ted Flanigan and Friends, 1976
The New DG: Rooftop Farming
DG in my world means “distributed generation.” DG is power generation at a small scale through solar, wind, geothermal systems, micro-hydro, etc. in the “fingers of the distribution system.” Rather than reliance on centralized power plants, replete with transmission lines strung over hill and dale, DG is the generation side of net zero.
DG is also about “distributed gardening,” and pushing agriculture and food production, like power generation, back into our communities. During World War II, 40% of fresh vegetables and fruits were grown in Victory Gardens scattered in the back yards of America. Now, the United States imports many fruits and vegetables from foreign countries. In response, there’s a return to local solutions and local food production. Brooklyn being touted as the “borough of farms?”
A new farm in Brooklyn, New York, in fact the largest rooftop farm in America. (I double take and think Bright Source.) Bright Farms will use a sprawling, 100,000 square foot rooftop of an abandoned 1.6 million square foot Navy warehouse to grow fresh produce for local markets and restaurants. To do so, they’ll build a 20-foot greenhouse structure on the roof of the eight story structure. Another farmer, the Brooklyn Grange, will open a similar 45,000 square foot operation at the Brooklyn Navy Yard. Yet another, Gotham Greens, plans three rooftop hydroponic farms in Brooklyn, Queens, and the Bronx.
“We’re bringing a business model where food is grown and sold in the community,” said Bright Farms CEO Paul Lightfoot in a New York Times article. Makes sense: there isn’t much open space for growing fresh produce in Brooklyn, but there are lots of warehouse rooftops. The Navy warehouse built in 1911 has been vacant since 2000. Its economic development focus is cultivating a light manufacturing hub. Urban farmers are pressing for city zoning laws to be changed to make it easier for commercial farms to “sprout” on urban rooftops, and to specifically exclude greenhouses from rooftop height and floor area restrictions.
The terms seem contradictory: Urban farming and farmers, urban agriculture and try this, urban livestock, and “planting food in food deserts.” It involves raised beds, container gardens, urban livestock, even “guerilla grafters” in San Francisco, an urban orchard in Seattle. The movement enables “quick travel time” for lettuce, tomatoes and other greens from garden to table.
Hydroponic operations are lighter than soil-based operations, making many rooftops eligible and structurally sound for growing fresh vegetables. Furthermore, the farms collect and use rain water, easing septic systems. The Bright Farms operation will capture 1.8 million gallons each year for repurposing on site.
Net Zeroes, Please!
Just love the term “net zero,” don’t you?
Reminds me of calorie-free soda, basketball, expensive and oversized refrigerators, and now some email permutation. In this case it involves net energy metering – using the electric utility as a bank and maintaining an average balance of zero, a credit/debit ratio of one. It also can involve offsets, selling excess good work and inversely buying pollution allowances.
Net zero energy buildings (NZEB) are the rage, soon to be mandated for all new construction. California will require such for all new homes beginning in 2020, all new commercial in 2030. In a mere eight years, every new home will have to provide for its own power.
What have the Army and Oberlin College in common? Net zero leadership. The Army, of all entities, is greenest in this category. It has a clear interest in net zero installations. Imagine being able to self-power, self-hydrate, and manage 100% of wastes in a hierarchy that leaves only a small fraction of materials for disposal. To the Army, net zero means three things: net zero energy, water, and waste.
At Oberlin College in Ohio, a solar parking lot pavilion, a fruit orchard on the north slope of an earth berm (25 bushels this year of apples, pears, and persimmons!) the Living Machine to treat waste waters, daylighting. Headed by David Orr at Oberlin’s Environmental Studies program, the new Adam Joseph Lewis Center was designed with the notion that human systems should mimic and integrate with natural ecosystems. Some consider it one of the most important green buildings constructed in the last 30 years.
The building community is all about net zero too! Meritage Homes announced the first production net-zero energy home in the country. Located in Buckeye, Arizona, the home is 3,391 square feet and features green measures including staggered 2*6 stud walls, high efficiency windows and HVAC, spray foam insulation, CFL and LED lighting, and 5.6 kW of photovoltaics. Meritage plans to work with prospective buyers on siting homes on lots to accommodate sufficient solar for net zero energy use.
Net zero now means both net zero energy and net zero cost. The trades are full of the design challenges to meet these dual, heretofore conflicting, objectives. A demonstration home in Pittsburgh proves that net zero can be built at net zero cost, “cash positive” from day one. The design and build teams used off-the-shelf products to build an affordable 2,100 square foot “Lab House” with advanced insulation techniques and heat recovery systems.
In Belfast, Maine, a super tight building envelope earned “the Go Home” an award. Passive house design, ultra-insulated shell, German born standard for GO Home, heating demands that are 85% less than standard, will save $170,000 in heating costs over 30 years. The “Go Home” features 2.8 kW of photovoltaics as well as evacuated-tube solar thermal. Included are exposed pine beams, locally quarried granite, and stained concrete floors.
Solar Air Conditioning
Counterintuitive isn’t it? But solar power can be used for air conditioning.
“Active” solar air conditioning is done either through “conventional” solar electric power generation, and then chilling, or through absorption chilling. The latter technology, advanced as it sounds today, pre-dates electricity.
Before there was power as we know it, natural gas was used as a heat source to create “ice batteries.” Using phase-change materials (ammonia, lithium, bromide), one end of an expansion/condensation tube is heated, the other gets cold enough to make ice. Today, a manufacturer offers a solar icemaker that features parabolic troughs and a no-moving-parts icemaker.
Solar cooling has gone high-tech, and concentrated solar power is being used to drive the systems since the most efficient absorption chillers need at least 190 F and most inexpensive flat-plate solar thermal collectors can heat to a maximum of 160 F. Parabolic troughs and concentrating systems are used with receiver pipes and heat transfer fluids to achieve these temperatures. Fresnel lenses are also used.
Despite its promise, solar air conditioning is new and has been relegated to demonstration. The Audubon Center in Los Angeles features solar air conditioning. Masdar City in the United Arab Emirates will be solar cooled, its central cooling plant made up of Sopogy, Mirroxx, and TVP equipment. The United World College in Singapore will feature the world’s largest system, rated at 1,500 kW.
One type of system scales down solar parabolic troughs to 1/3 the size of utility-scale, power installations. Sopogy, a Hawaiian company whose name was developed from “Solar, Power, Technology” uses concentrated solar, mirrors and parabolic troughs, to heat fluids to spin turbines to generate power for air conditioning.
America's Largest Rooftop Solar Plant
The photovoltaic plant is so big that a U.S. Representative came all the way from Washington with an $11 million federal tax credit rebate. The Gloucester Marine Terminal is the largest rooftop solar power plant in North America. The project is on top of the refrigerated warehouse near the Walt Whitman Bridge over the Delaware River. The warehouse operates on a 24/7 basis to service food importers and is the largest “on-dock refrigerated warehouse” on the East Coast.
Known as Riverside Renewable Energy, LLC, the 9 MW, $42 million project in Gloucester City, New Jersey, consists of 27,526 photovoltaic rooftop solar panels covering 1.1 million square feet of rooftop. A total of 200 construction workers were involved in the construction; it will generate 80% of the Terminal's power demand, offsetting 8,100 tons of carbon dioxide each year.
SunPower built the project. It was supported by federal and state tax incentives and the N.J. Solar Renewable Energy Credit (SREC). Riverside will sell the SRECs associated with the system “to enhance the economic viability of the project.” Many obstacles such as its high-wind location along the Delaware River, the oversight of the Terminal by the Department of Homeland Security, and the fact that the Terminal is a federal Environmental Protection Agency Superfund site, ratcheted up costs. Construction on the solar project began in June 2011 and was completed on budget and ahead of schedule.
UK Carbon Capture Contest
A lump sum of one billion British pounds is on the table for a company or consortium in the United Kingdom to demonstrate and implement an effective carbon capture and storage (CCS) mechanism. While some English are dismayed with the contest process, one that has been tried to reach fruition since 2007 and failed six months ago when a consortium led by Scottish Power could not reach financial terms with the government, the incentive remains one of the largest prizes ever for a single project.
Furthermore, the United Kingdom has committed 125 million pounds for ongoing research and development, including a new U.K. Carbon Capture and Storage Centre, perhaps the largest in the world, according to the chief executive of the Carbon Capture and Storage Association.
Worldwide, governments have put their muscle behind CCS, some $40 billion thus far according to the U.K. Department of Energy and Climate Change. Since the UK prize as conceived, demonstration plants have been built. Now seven consortiums are reportedly “lining up” for the prize money. The first time round, only means to clean CO2 from emissions of coal plants was allowed. This time, pre-combustion mitigation measures are also eligible, as are gas-fired plant emissions schemes. Proposals are due in early July.
Italian Feed-In Update
Getting the price right for solar incentives is tough. Europeans have erred on the side of being generous, perhaps overly generous. And the results are in and they are positive. Lots and lots of solar capacity has been installed in Europe thanks to the simplicity and prices of its feed-in tariffs. Americans have been far more stingy, especially with feed-in tariff prices, and the returns are proportionately small.
Generous feed-in tariffs get results. We had a banner year for commercial solar in America using more traditional incentive structures and installed 2 GW across the country. Despite recession, debt crisis, and government turnover last year, Italy installed 9 GW. Sure, the Italians have to cut back, last year was a “solar boom,” but perhaps we take note. To stimulate a market and succeed, one can err on the side of generosity. Then you “degress” and reduce your posted tariff prices gradually. Italy has reduced its prices significantly, while maintaining its industry support with tariffs and premiums for EU sourced materials (60% requirement), school and hospital systems, and building-integrated photovoltaics.
Italy’s whopping, nine-month solar success is having repercussions. The incentive resulted in solar capacity that exceeded its 8 GW national goal for 2020. Its biggest utility, ENEL, is now is fearful on two fronts. Its conventional power plant investments are “stranded” and the company is being burdened with additional high-cost renewable capacity. As its Chairman reports, ENEL has been hit by the excessive costs of the development of renewables, coupled with stagnation of demand. Solar and wind now make up 26% of Italy’s electricity production. Some estimates suggest the feed-in tariffs paid to photovoltaic generators will be as high as $59 billion over the next 20 years.
Environmental Benefits of Vegetarianism
The benefits of vegetarianism are immense for individuals and society. Take lower blood cholesterol, less obesity, a lower death rate related to heart disease, and less hypertension. Tough sledding arguing the alternative.
The environmental and social benefits are enormous: It takes 10 pounds of plant material to produce a single pound of meat, an unfortunate conversion ratio given world hunger. Animal production is land intensive too, destroying habitats in some countries.
Producing animal protein is eight times as fuel intensive as an equivalent amount of plant protein. It takes 400 gallons of fuel to produce the meat consumed by the average American. That’s equivalent to a 10,000-mile carbon footprint (20,000 miles for Prius drivers).
And all that before 1.5 - 2 billion tons of manure worldwide each year, an EPA top pollutant from an industry known for methane production its magnified greenhouse gas impact.
So who’s vegetarian?
The most vegetarians in the world are in India, some 399 million driven by culture and religious concerns. Studies show that 31% are strict vegetarian, another 9% eat eggs. In the United States, some 7.3 million Americans are vegetarian (3.2%), though 10% are “vegetarian-based diet inclined.” Vegans who eat no animal products number about a million, a fraction of a percent of Americans.
Mad Cow Disease scared many Europeans. Now 6% of the British are vegetarian, with twice as many women as men; 10% eat no red meat. The European Union vegetarian rates range from 0.3% in Portugal to 4.3% in The Netherlands. In China, vegetarianism is rare, although devout Buddhists practiced it years ago. In 2010, Prime Minister Wen Jiabao proposed a national campaign for one day of vegetarianism every week.