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Sheldon A Harrison
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SD, No, most transit trains in this class could not easily run on batteries. The Germans are masters of understanding technical requirements and concluded that H2 is necessary for the service patterns of this route. The route is about 80+ miles long between Cuxhaven and Buxtehude via Bremerhaven and Bremervorde. The current LINT service turns around at the end and does not allow enough time to fully recharge at the electrical power typically available at these locations. Batteries are seriously limited even for applications less demanding than NA diesel freight. 600 KWH would not allow these trains to run all day given the relatively high speeds (60 - 80 mph) and the needs for hotel loads (HVAC), especially in winter in Germany. Proterra buses as well as BYD suffer the same problem with hotel loads and being able to regularly complete daily shifts and it gets worse as the batteries age.
@WillyG Hydrogen storage and the associated power conversion equipment (aka fuel cells) especially in a truck is lighter for a given energy storage capacity than is the same for batteries. The weight of the compressed gas cylinders (5 - 6% H2 storage by weight equating to 2,000kg of cylinder weight for 100 kg of H2 stored ) plus fuel cell is easily 1/3 of what can be achieved with batteries. 100kg equates to over 3,000 MWH stored and even after accounting for the 50 - 60% efficiency of the fuel cell, still accounts for more than 1.5MWH. To store 1.5 MWH in a battery using state of the art cells at 300 wh/kg, 5,500 kg will be required. Note, batteries used in trucks where long life and durability are desired will not achieve 300 wh/kg but a more realistic 200 wh/kg meaning the weight increases (up to 8,000 kgs) accordingly. Even accounting for another 200-400kg of buffer batter and fuel cell weight, we are still 1/3 of the weights achievable by batteries.
The governments recognize that H2 can be more than a niche or partial solution. There is no technical reason (no fundamental breakthroughs needed) that it cannot be applied at every scale you care to imagine and in every facet of the industrial energy economy. Conversely, BEVs have technical characteristics that will make them unacceptable for some users. They lack the flexibility of use as the current paradigm, particularly re speed of recharge.. Anyone requiring maximum uptime of an expensive capital asset will not be pleased. The charging time limitation is a very real issue. Battery prices have indeed come down significantly over the last decade but expecting the same trend to continue is not wise. There is a very intense debate about the lower limit of battery price reductions given that we keep hearing about breakthroughs yet still are stuck with Li_ion which cannot get much below $100 per KWH with known, lab technology. Current Li-Ion lab technology has raw material inputs alone at best case $40 - 50 per KWH implying that any additional processing makes a number lower than $100 for a fully integrated battery extremely unlikely. We need a different chemistry for that. If we do not get to a max of $50 per KWH at the pack level, BEVs will be behind the ICEV price for somewhat similar usability. I consider equivalent usability to be the ability to travel 350-400 real highway miles (5 - 6 hours of travel) at the 75-85 mph prevailing travel speed of rural Interstates and the ability to be recharged in 10 minutes or less. When those conditions are met, the vehicle range/refueling characteristics won't need considered when planning long trips as is the case today with ICEVs,
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Nov 13, 2019