In this second part of our chat with Honda's Stephen Ellis we continue our discussion of the Honda Home Energy Station and get into the costs and practicality of hydrogen as a fuel. Read part one here.

ABG: What kind of efficiency are you are looking at right now for the Home Energy Station? How long does it take to produce how much hydrogen? How efficient is the process? How would the cost of operating such a device compared to what we use today?

SE: I think Home Energy Station puts into perspective that here we are now removing the tail pipe from the equation of emissions and now looking to the upstream. So whether it is the energy to charge an electric vehicle, a plug-in hybrid or to fuel any other car we have to look to the upstream.

Home Energy Station is a research project still that is targeting these efficiencies such that we have this near 50 percent CO₂ reduction on a well-to-wheel basis when matched with hydrogen fuel cell car. And that is again taking advantage of these efficiencies. Today, using steam methane reformation of making hydrogen from natural gas in these large plants, we have shown this graphically that we have over 50 percent CO₂ reduction when combined with the FCX. This new FCX using that same process now will moves that to 60 percent. So that's a step in the right direction.

(Q&A continues after the jump)

Alongside the debut of the 2009 FCX Clarity, Honda also showed off the latest fourth generation version of their Home Energy Station (HES). The concept of the HES is to provide a self-contained unit to use a home's natural gas supply to heat the house, heat water, produce electricity and fuel a hydrogen car. The HES unit includes a steam reformer system to produce hydrogen from the gas, and a fuel cell of its own to provide electricity for the home. According to Honda's Stephen Ellis, using this system to generate hydrogen and fuel an FCX can reduce total well-to-wheel CO₂ emissions by sixty percent compared to an equivalent gasoline-fueled car. Such a system is unlikely to be ready for home use before the middle of the next decade at the earliest, but if and when it does become practical it could provide a viable way to mitigate the problem of a hydrogen fueling infrastructure.

[Source: Honda]