I came across an interesting company recently, Adura Systems in Silicon Valley. The company is designing a bus that it says can get 100 miles on a single charge. More if you make it a hybrid.
It's still in the development stage -- and is hiring engineers, if you're interested. Adura recently closed a bridge financing from New Frontier Renewable Energy LLC, a clean tech fund.
Adura's differentiator is that it's building an electric power-optimized drive train from the ground up rather than adding electronics and batteries to an existing gas-powered design. The idea is to replace mechanical complexity with complex electronics and software - electrical rather than mechanical interfaces between systems. The generator has only one moving part, compared to over 100 for ordinary generators.
Modular battery design.
While Tesla uses a 7,000-cell battery with a 55 KWH charge, Adura uses multiple 22 KWH batteries, fitting up to 10 on a bus. Pull them out to recharge and replace with fresh one. Use fewer batteries of you're going a shorter range (the company also plans to use the design in commercial trucks.) Each "smart" module (batteries, electric generator and motor) can coordinate its power usage with the rest of the system. Load balancing systems pull power from the batteries with the best charge when some start going out, or automatically adjust to more or fewer batteries.
Cheaper?
The problem with most EVs is added cost. Adura management claims their redesign and simpler mechanics makes their vehicles cheaper, anticipating a volume price of $155K compared to $180K to $250K for other electric vehicles. They also say cost of maintenance is reduced to $0.20 per mile, from $1 per mile for other large vehicles.
Why a bus?
The reason Adura is doing buses is because it found a market -- China. The founders started out with the idea of doing trucks (and can still do that) but they were put in touch with the China Automotive Technology and Research Center (CARTARC) the Chinese equivalent of the U.S. Dept of Transportation.
Adura got an endorsement from CATARC to sell to Chinese bus manufacturers. China wants to clean up its image and show off clean buses to tourists. One manufacturer in Guangzhao is interested and is now sending Adura a bus to prove the concept. Adura will replace the drive train with its own. So far the company just has a small one-person vehicle to prove the concept. I drove it. It's cool.
Will it work?
I don't know. The interest from China is promising, and it has won several kudos and awards. But I've noticed that several of the technical people have left the company recently, such as the former chief architect, Jim Caselaz, who was CTO of a Stanford EV project and Graduate Fellow in Stanford's EE PhD program. And this is still early stage, with a lot to prove.
Adura is headed by Marv Bush, former founding partner at Ovo Technology Partners, a seed stage investor. He was also CTO of Coyote Systems and Translogic Technology, and a former exec with Cadence and Tangent.