However, the ultracapacitors are much more abuse-tolerant to higher temperature ranges, they don’t catch fire, and they’re more recyclable. They’re 95 percent-plus recyclable and it’s very inexpensive to recycle the capacitors, typically about 35 cents per pound. When you look at batteries, lead acid batteries have been recycled for a number of years but they are only about 70 percent recyclable. And lithium ion batteries, there are a number of batteries out there that are used, but they just aren’t being recycled today.
Hall says in the last 10 years the cost of ultracapacitors has come down approximately 90 percent and at the same time, performance has gone up five times. Battery costs have also come down and performance has gone up, however a bit more slowly. “You are getting about a five times better performing product at about 10 percent of the cost of what you would have gotten 10 years ago. In that same range battery performance has gone up maybe 10 percent and their price has only come down about 30 percent.”
Orberger says that globally, the United States has the highest penetration of alternative powertrains, more than Europe and more than China. He says the reason for this is because OEMS in Europe have optimized their transmissions and engines to gain fuel economy and reduce emissions over the last 10 years. “The reason for this is OEMs like Mercedes-Benz and other larger OEMs manufacture engines and transmissions, they have a vested interest, profit margins, the transmissions and engine.”
The difference in the United States is bus OEMS here don’t manufacture engines or transmissions, according to Orberger, so they don’t necessarily have a vested interest to change the powertrain and technologies used.
He says: “They are much more open to the depth and adjust to new technologies and to pass new technologies in order to save fuel and to reduce emissions and optimize fuel consumption. I’m a firm believer that this was the starting point here in the U.S., to adapt much earlier alternative powertrains and this is providing the U.S. basically a jumpstart ahead of the Europeans. The Europeans right now they are trying to catch up. They are now embracing hybrid technology and time will tell how quickly they catch the U.S.”
According to Orberger, 50 percent of the attributed costs of a hybrid bus are energy storage and the remaining 50 percent is the equipment, motors, generators, etc. He says prices are coming down for both energy storage and the other remaining equipment.
“What we at Siemens do, we have a global portfolio base so every order impacts on our supply chain, which has a positive impact on North America. If you have an order in China for 10,000 vehicles and we increase our economy of field, this is a direct impact on our cost base we have here in the United States to reduce our costs here as well. That’s one of the large benefits of a global organization like Siemens being active in this marketplace and every economy of scale has a global impact on this.”
He continues: “On the battery side, Siemens has decided to move and build our energy storage unit on ultracapacitors. That is part of our portfolio, so we have a direct impact and a direct control over our costs. It’s still expensive, but we have a handle on this and then the potential for Siemens to go into the battery packaging market.”
BAE Systems has been developing hybrid propulsion systems for 20 years, according to Mekhiche. BAE Systems’ HybriDrive series architecture is designed to support the needs of bus in an urban downtown area that is low speed and requires a lot of stop-and-go operations.
“In a series system you no longer use the engine to drive the wheels. There’s a small engine that drives a generator, and the generator makes electric power and that electric power is then provided through wires to another electric machine that then spins the wheels. It’s all electrically driven,” Mekhiche says.
BAE Systems has demonstrated up to 40 percent fuel savings in the field with the series system. “So a hybrid bus that uses our hybrid series system would save on average 40 percent on fuel in service. Plus it gives you all the emissions reductions and quieter operation that you would need to meet the standards but also to enhance the environment in cities and crowded urban areas and so on,” explains Mekhiche.