In the Marx Brothers comedy classic Duck Soup, Groucho as a nation’s president said, “Why a four-year-old child could understand this report. Run out and find me a four-year-old child. I can’t make head nor tail out of it.”
When it comes to zero-net-energy (ZNE) buildings, children are leading the way. In one year, a ZNE building generates with its own renewable energy the equivalent energy it consumes in that year. Typically, some months a ZNE building is generating excess electricity that is supplied to the grid, other months a ZNE building is using electricity from the grid.
After ZNE homes, schools have more ZNE buildings than any other sector of our built environment. There are 100,000 public schools in the U.S, so we are just getting started. Currently, children miss 14 million-school days due to asthma and lung diseases. In ZNE buildings, children are absent less and learn more due to better lighting, natural daylighting, and use of more healthy materials.
We need to invest more in education. These children are our future in a competitive global economy. Currently, U.S. schools, kindergarten through twelfth grade (K-12), spend $8 billion annually on energy, more than on computers and textbooks combined. Over a 20-year period, energy efficiency and renewables save billions that can be invested in better education. RMI Report
Schools Lead in Zero Net Energy
The Energy Lab at Hawai’i Preparatory Academy is ZNE and the first K–12 school facility to achieve “Living” certification through the Living Building Challenge (LBC) by harvesting at least as much energy and water as it uses over the course of a year, using low-impact building materials, and producing zero waste. It’s great for learning, with strong use of natural lighting and ventilation. The science building houses classroom and meeting spaces for a school curriculum focused on renewable energy, and includes rainwater harvesting, onsite wastewater treatment, and a 26 kW photovoltaic array. NBI Report
Locust Trace AgriScience Farm is a ZNE-certified technical high school near Lexington, Kentucky. In addition to preparing students with English, science, math, all the needed core courses, Locust Trace provides hands-on training in agriculture with spacious classrooms with adjoining labs, 6.5 acres for gardening, a state-of-the-art greenhouse with an aquaculture area for raising fish, an equine barn and arena, and an on-site veterinary clinic. Roofs are graced with 175kW of solar PV. Three separate zones are heated and cooled only as needed, using a dual-stage water source heat pump and an energy recovery dedicated outside air unit. Since the building has much higher heating loads than cooling loads, solar thermal radiant heating system is included and produces an average of 40,000 BTU per day.
When my grandfather grew up in Kentucky, it was a coal state. Now coal jobs are at the lowest level in 118 years, with 6,900 working in the coal industry. Yet there are 74,000 construction workers in Kentucky, with more creating high-performance buildings than those that ever worked in coal. Kentucky is showing ZNE leadership in schools.
Big Impact of Lighting, Heating, and Cooling
For most school districts, it is easier to start with one ZNE building, rather than with an entire campus. It could be a library, environmental center, music building, or district office building. ZNE is easier to accomplish in a new building than in retrofitting.
In a typical school building, 30 percent of energy is for lighting. LED lighting uses only a fraction of the energy of older lights. Add low-cost sensors and controls, and lights are automatically turned-off when no one is present. Design classrooms to make good use of natural light and students learn more, have less behavioral issues, and use even less electricity. Studies have documented 20 to 26 percent test improvements in natural daylight environments.
In a typical school, 35 percent of energy is for heating and cooling. More schools, like Hawai’i Preparatory, use good passive design to orient the building for warmth in winter and cooling for hot days, and make best use of natural ventilation; more learning, less energy. HVAC demands are minimal in buildings with well-insulated walls, roofs, and windows. With ground source heat exchange, HVAC can often be eliminated.
The Collaborative for High Performance Schools (CHPS) is the United States’ first green building rating program especially designed for K-12 schools. CHPS provides information and resources to schools in order to facilitate the construction and operation of high performance institutions. A high performance school is energy and resource efficient as well as healthy, comfortable, well lit, and designed for a quality education.
Many states have excellent programs. For example, the California Clean Energy Jobs Act of 2012 (Prop 39) provides up to $550 million per year to improve energy efficiency and increase the use of clean energy in public schools and community colleges. The Prop 39 ZNE Schools Pilot assists schools in retrofitting existing facilities to ZNE. By 2025, all new government buildings in California must be ZNE. By 2030, California will be 50 percent renewable energy.
University of California = Carbon Neutral 2025
The UC Carbon Neutrality Initiative is dedicated to achieving net-zero greenhouse gas emissions by 2025 across all 10 UC campuses. This is ambitious due to the energy demands of over half a million people, power-hungry research labs, and hundreds of buildings. Yet, the UC system is already a model example of clean energy.
The University of California Irvine, my alma mater, was ranked No. 1 in Sierra magazine’s “Cool Schools” ranking of the nation’s greenest colleges. Buildings are energy-efficient, with over 20 buildings LEED Platinum and Gold. When I visit the campus, solar roofs and parking structures are visible everywhere.
Sister campus, UC San Diego, saves over $10 million annually in utility bills by generating its own electricity with solar, 30 MW of combined heat and power, and fuel cells. The campus has its own substation and microgrid and with multiple thermal and battery storage systems.
The UC Carbon Neutrality Initiative is also inspiring the communities of the 10 UC campuses. Near UC Davis, two thousand people live in the ZNE community of West Village in Davis. The project includes 662 apartments, 343 single-family homes, 42,500 square feet of commercial space, a recreation center and study facilities.
The Davis homes are super efficient and typically use solar power. Energy efficiency is achieved with tight construction, triple pane windows, great insulation everywhere, Energy Star appliances and LED lighting. These homes are designed and ventilated to stay cool in the summer and warm in the winter. Heat pump and space cooling is used instead of energy-hungry conventional HVAC. With excellent energy efficiency, solar power can meet most energy needs.
Other UC solutions include an 80 megawatt solar array in the Central Valley (the largest at any U.S. university), an experimental anaerobic digester that is using food waste to produce bio-methane, a molten carbonate fuel cell that generates 2.8 megawatts of electricity from municipal wastewater treatment emissions, smart lighting and smart building systems, and a solar greenhouse that selectively harvests light for solar electricity. Research labs may need air conditioning at the same time that classrooms need heating. Intelligent heat exchange can dramatically reduce the energy for heating ventilation and air conditioning systems (HVAC).
From a first grader, learning more in a naturally lighted and ventilated classroom, to a new university graduate eager to make the world better, students are increasingly experiencing that all our energy needs can be meet with zero-net energy.