ACHRNEWS

Welcome Back, Solar Heating-Cooling

November 12, 2007
Texas A&M University’s solar-powered home incorporated interchangeable rooms, so occupants could change the home to suit their needs, a feature the team shared with visitors to the Solar Decathlon on the National Mall in Washington last October. (Photos by Kaye Evans-Lutterodt/Solar Decathlon.)


If you thought solar heating-cooling all but died with tax credits in the 1980s, you’d better think again. Renewed interest in lowering buildings’ carbon footprints, reducing energy bills, and generally reducing energy consumption has renewed the interest in technologies such as solar heating, cooling, and power production. Interest from government and investment sectors are a few positive indicators for the technology.

It has caught the interest of investment firms like Piper Jaffray, which held a Solar Symposium in Long Beach, Calif., in September. “If it wasn’t clear to our nation before, it is clear now that energy is one of the most critical issues for America,” said Office of Energy Efficiency and Renewable Energy Chief Operating Officer Paul Dickerson, addressing attendees of that conference.

“How we obtain it [energy], how much we pay for it, and how we consume it are all questions we face on a daily basis,” he said. “And what’s nice is, for the first time in our lives, being green is not a partisan issue. Whether you care about the environment, national security, or the economy, we all want the same result: clean, green, secure, and affordable energy sources.”

In 2006, he said, the investment in sustainable energy was $71 billion, “an increase of more than 40 percent; 2007 looks even better. Of that $71 billion, my office invests $1.5 billion of [U.S] tax dollars. Our goal is to invest that money in more focused and smarter ways. To do so, we have stepped up our dialogue with the world’s scientists, engineers, and business leaders in search of investment tipping points.”

MONITORING, MAINTENANCE

Controls innovations are a fine example of alternative energy system advances. Sensicast Systems Inc., Needham, Mass., announced that its SensiNet® wireless sensor offers a system for “string-level” monitoring of photovoltaic (PV) solar power. The announcement was made at the Solar Power Conference and Expo.

The product is based upon the newly available SensiNet dc voltage and current smart sensors for string-level monitoring of PV solar power-generating systems. Housed in NEMA-4 enclosures for outdoor use, the sensors work in concert with other SensiNet components, including temperature and humidity sensors, mesh repeaters, gateways, and software, to provide a system for metering and monitoring commercial solar electric systems.

Energy-conscious builders are showing more interest in PV solar-derived electricity because its low carbon footprint makes it an attractive renewable electricity source to power lighting, appliance, and equipment operation, even electricity-intensive systems such as HVAC and hot water, stated the manufacturer.

SensiNet monitors the operating efficiency of PV systems by capturing real-time data, the company said, reflecting the condition of PV cells and panels, and detecting problems that may lead to inefficient operation. It automates the monitoring process and reports the level of energy production, logging and notifying maintenance personnel, and producing automatic maintenance dispatches.

“Investing in systems that support the efficiency and reliability of renewable energy gives businesses tangible financial, operational, and environmental benefits,” said Gary Ambrosino, CEO of Sensicast.

“By automating the task of detecting problems and dispatching maintenance personnel with information on their precise location and cause, Sensicast eliminates the time-consuming, often painful search and identify mode of fixing PV arrays and panels in use today.”

Through its ability to monitor and report PV system conditions and make data available to building automation applications, the sensor system offers a way to maximize the efficiency of solar systems used for energy self-sufficiency and revenue production. It can be easily integrated with other SensiNet systems for building monitoring, the company said.

The first installation of the PV solar monitoring-control system in a production network is being jointly carried out by Live Data Systems and Sensicast at the new, 42,000-square-foot headquarters of Ferreira Construction Inc., Branchburg, N.J. This building uses a combination of eight components that either produce energy or reduce the building’s energy needs.

The building is said to be on track to meet the Department of Energy’s (DOE’s) goal for a “Zero Energy” building by 2008. The Ferreira Construction facility includes 1,200 solar panels (electric), solar thermal (hot water), a 96 percent-efficient boiler system, and a radiant-slab heating system.

The Georgia Institute of Technology’s Solar Decathlon home played with light to transform and open up living spaces, as displayed at the Solar Decathlon on the National Mall in Washington.

INVESTING IN THE FUTURE

The many benefits of solar technology were displayed as working systems at the DOE’s Solar Decathlon competition. It took place in October on the National Mall in Washington, where 20 university-led teams from the United States, Puerto Rico, Spain, Germany, and Canada designed, built, and operated solar-powered homes.

The students competed in 10 areas, ranging from architecture, livability, and comfort, to how well the homes provided energy for space heating and cooling, hot water, lighting, and appliances. Technische Universität Darmstadt, from Germany, earned 888.45 points out of a possible 1,200 to win the competition, followed by the University of Maryland team with 872.45 points, and the Santa Clara (Calif.) University team with 860.80 points.

During his congratulatory remarks, Energy Secretary Samuel Bodman announced funding of more than $44 million to support the commercialization and promotion of advanced solar and other clean energy technologies.

“Promoting the early commercialization of solar and other energy-efficient technologies will help secure America’s clean energy future.”

Four Building America contractor teams, including the Building Science Corp., Consortium of Advanced Residential Buildings, and Building Industry Research Alliance, will receive up to $40 million over the next five years to develop net-zero energy homes. These homes will be designed to use 70 percent less energy than homes built to current codes, and will incorporate solar or other onsite renewable systems to provide the balance of their energy needs, according to the Decathlon organizers.

This funding is part of the Building America program, a private-public partnership sponsored by DOE that conducts systems research to improve overall housing performance, increase housing durability and comfort, reduce energy use, and increase energy security for homeowners.

Secretary Bodman also announced two regional building technology application centers, at the University of Central Florida and Washington State University, that will serve 17 states. DOE awarded $4.1 million to accelerate the adoption of new and developing energy-efficient technologies by the market. These centers will deliver information and training on commercially available energy-saving technologies, processes, and tools, and provide a regional resource for market changes.

The Solar Decathlon is said to complement President George Bush’s Solar America Initiative, the goal of which is to make solar energy cost competitive with more conventional forms of electricity by 2015.

“The Solar Decathlon helps develop the future of sustainable engineering for the building industry,” said Kent Peterson, president of the American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE). “The knowledge and dedication of these students will help ensure that today’s interest in sustainable technology and renewable will propel the building industry into brilliant possibilities for the future.”

For more information, visit www.sensicast.com, www.livedatasystems.net, and www.solardecathlon.org.

Publication date: 11/12/2007