Re: Let’s Talk Candidly About Energy
Posted: Wed 31 Jan 2018, 13:03:20
I would interject another dose of reality here. The VTA (Valley Transportation Authority) in Santa Clara Valley (larger than and containing Silicon Valley) recently completed (2013-2015) evaluation of alternative bus powertrain technologies for the streets portion of their mass transit system. They were interested in replacing their aging fleet of conventional diesel powered busses, and VERY interested in eliminatating carbon emissions from the valley if at all possible.
It wasn't possible. The alternatives in the 2 year test were:
1) New technology diesel powertrains with DEF (Diesel Exhaust Fluid) injection to reduce emissions.
2) New Tech diesel with DEF and Hybrid (electric battery) powertrains.
3) Flywheel mechanical energy storage between bus stops.
4) Hydrogen fuel cell electric busses.
5) Lithium BEV powertrain.
6) Compressed natural gas with ICE spark motor (i.e. NOT diesel).
7) Overhead electric trolley (similar to the light rail they also run, and a favorite contender).
(I think that's all, but I didn't look it up, that's from memory.)
They gave a fair 24 month test including maintenance, but they deliberately decided to exclude the infrastructure buildout. There was one bus route with flywheel winders, one hydrogen filling station at a VTA maintenance yard, and one route with overhead trolley wires.
#2 (New Tech diesel with hybrid power plants) was the hands-down winner. Hydrogen was exposed as more suitable for NASA than VTA, and CNG was a distant second place contender, relatively low in carbon emissions. I followed this testing for two years and I'm satisfied that it was even-handed and fair, including costs apportioned for carbon emissions in all cases.
These are replacing the bus fleet:
....and fortunately for the taxpayer, the infrastructure for the existing conventional busses is pretty much the same as required for the Hybrid new tech diesels, with the addition of DEF distribution, and the need to fill up two tanks (one of diesel fuel and one of DEF).
Expected savings are 25% of the fuel consumed by conventional busses, and about half of the carbon emissions. The new Hybrid busses have a purchase price of $400,000 in the small size, up to $600,000 for the larger articulated busses used as airport parking shuttles. Just for comparison, the hydrogen busses fell from $3.5M in 2013 to $2.5M in 2015, after significant re-design that invalidated the maintenance cost analysis for hydrogen.
THIS is the type of infrastructure renewal that makes dollars and sense today. Don't forget that the VTA had already completed a light rail system (similar to but newer than BART in SF) and was really really motivated by SIG Alerts (i.e. smoggy days which required every possible person to telecommute). Most urban areas would require construction of both the electric trains and the purchase of a new bus fleet ($$$$).
The very bad news: Today with the new Hybrid busses, the system is 100% powered by petroleum. There is not enough biodiesel in the whole state to power this one urban transit system. Not to mention, we also have the older conventional diesel-electric commuter trains in the valley still (CALTRAIN and AMTRAK).
It wasn't possible. The alternatives in the 2 year test were:
1) New technology diesel powertrains with DEF (Diesel Exhaust Fluid) injection to reduce emissions.
2) New Tech diesel with DEF and Hybrid (electric battery) powertrains.
3) Flywheel mechanical energy storage between bus stops.
4) Hydrogen fuel cell electric busses.
5) Lithium BEV powertrain.
6) Compressed natural gas with ICE spark motor (i.e. NOT diesel).
7) Overhead electric trolley (similar to the light rail they also run, and a favorite contender).
(I think that's all, but I didn't look it up, that's from memory.)
They gave a fair 24 month test including maintenance, but they deliberately decided to exclude the infrastructure buildout. There was one bus route with flywheel winders, one hydrogen filling station at a VTA maintenance yard, and one route with overhead trolley wires.
#2 (New Tech diesel with hybrid power plants) was the hands-down winner. Hydrogen was exposed as more suitable for NASA than VTA, and CNG was a distant second place contender, relatively low in carbon emissions. I followed this testing for two years and I'm satisfied that it was even-handed and fair, including costs apportioned for carbon emissions in all cases.
These are replacing the bus fleet:
....and fortunately for the taxpayer, the infrastructure for the existing conventional busses is pretty much the same as required for the Hybrid new tech diesels, with the addition of DEF distribution, and the need to fill up two tanks (one of diesel fuel and one of DEF).
Expected savings are 25% of the fuel consumed by conventional busses, and about half of the carbon emissions. The new Hybrid busses have a purchase price of $400,000 in the small size, up to $600,000 for the larger articulated busses used as airport parking shuttles. Just for comparison, the hydrogen busses fell from $3.5M in 2013 to $2.5M in 2015, after significant re-design that invalidated the maintenance cost analysis for hydrogen.
THIS is the type of infrastructure renewal that makes dollars and sense today. Don't forget that the VTA had already completed a light rail system (similar to but newer than BART in SF) and was really really motivated by SIG Alerts (i.e. smoggy days which required every possible person to telecommute). Most urban areas would require construction of both the electric trains and the purchase of a new bus fleet ($$$$).
The very bad news: Today with the new Hybrid busses, the system is 100% powered by petroleum. There is not enough biodiesel in the whole state to power this one urban transit system. Not to mention, we also have the older conventional diesel-electric commuter trains in the valley still (CALTRAIN and AMTRAK).