The ZESS 50 fuel cell made by Menomonee Falls-based ZBB Energy Corp. will be part of the Zero Net Energy Future House USA home, which will be displayed during this summer's Olympic Games in Beijing, China. The ZESS 50 fuel cell is an energy storage system similar to a battery. However, the cell's design is different than a traditional battery, with fluid charged with electrolytes flowing past its cell membranes, said Kevin Dennis, vice president of sales and marketing for ZBB.

"There are a couple of advantages (with this design)," he said. "Once the cell is charged, you can turn it off. A battery is always on." ZBB's fuel cells are designed for large energy efficient homes, commercial and industrial properties and power relay stations. When they're not in use, ZBB Energy's fuel cells discharge at a much slower rate than batteries, Dennis said. The fuel cells are rechargeable, and can be recharged many more times than rechargeable batteries. "We design fuel cells like this on the order of 20 to 30 years," he said. "You will have to replace the (cell) membrane in about 10 years. The cycles are on the order of thousands."

The ZESS 50 is ZBB Energy's 50 kWh energy storage module. ZBB Energy also makes the ZESS 500, which can store up to 500 k Wh. ZBB Energy has piloted its fuel cells for the past four years, Dennis said, and began production earlier this year. The company, which has 38 employees, manufactures the fuel cells from its 72,000 square foot facility in Menomonee Falls.

The Future House USA will be part of the Future House Village, a neighborhood of eco-friendly demonstration homes created by teams from Canada, China, Germany, Japan, South Korea, Spain, Sweden and the United States. The high-visibility program is designed to promote energy-saving strategies and construction that will have a minimal impact on the global environment.

"Our participation in the Future House USA project is part of our long-term plan for ZESS to be used in residential applications," said Rob Parry, CEO. "This project presents the perfect opportunity to introduce the ZESS product into the China market. What better forum for us than to be part of the USA entry into this sustainable housing project being unveiled to the world at the Beijing Olympics?"

The ZEZZ 50 also works well for the project because many of its materials are more environmentally friendly than what is found in traditional batteries. The cell membranes and cell sacks are made from recyclable high density plastic, Dennis said, and the fluid used in the fuel cells has a much lower acidity level than most batteries. "It's still acidic, however the pH is on the order of Coca-Cola," he said. "If there is a spill, you just put baking soda on it."