Fuel Cell Vehicls (FCVs)
Although the credit has been decreased to the BEV-equivalent since Obama era, FCV is much more sustainable than BEV as pointed out in the Bush Jr. era: water is not exhausted but regenerated unlike metal resources.
Wind power needs hydrogen production to storage a large amount of energy that cannot be stored by using batteries in a cost-effective manner. The research has been calculating the hydrogen production cost: it would be JPY20-30/Nm^3 (1/3 of the gasoline cost in Japan) by using the current electric power system network including regenerative energy with a small amount of decoupling capacity that would be batteries. Note that the current regenerative energy still needs thermal power back up.
(cf.) Perhaps wind power is going to be equipped with the hydrogen production facility and PCFC (Protonic Ceramic Fuel Cell). In addition, PAFC (Phosphoric Acid Fuel Cell), which has already been commercially used for on-site power generation, also exhibits the 70% of power generation efficiency, thus, it would be used in a complementary manner. AFC (Alkaline Fuel Cell), which also uses pure hydrogen as the fuel, can also be used in addition to PAFC.
However, how can Fuel Cell Vehicles (FCVs) spread, particularly in the passenger vehicle sector?
(cf.) We should leave room for small BEVs, e.g., equipped with a 10-kWh battery pack that do not run 100 km a day that does not need a heavy battery pack to be carried that is much heavier than passengers.
(1) FC-stack cost must be decreased. One detour can be FC/battery ratio reconsideration.
(a) Toyota (FC-HEV)
Toyota has been using a 1.3-kWh Ni-MH battery pack that costs JPY130,000 + wages of JPY40,000-50,000, thus JPY170,000-180,000 in total.
he FC stack is 114 kW that is placed in the center of the chassis. It costs JPY2,280,000 (planned to decrease to JPY570,000 by 2025). Therefore, the battery/stack cost becomes JPY2,450,000-2,460,000.
The shift from ICV-HEVs to FC-HEVs can be a scenario for the future zero-emission mobility. However, the cost is still high.
(b) Renault (FC range extender)
Renault uses a 33-kWh Li-ion battery pack and a 5-kW FC stack that can cost JPY880,000 and JPY50,000, respectively; thus, JPY930,000 in total.
(cf. 1) Nissan Leaf with a 30-kWh Li-ion battery pack. The battery-pack weight is 310 kg.
(cf. 2) China has been producing FC range extender buses and trucks, the much better choice for large vehicles than BEVs.
Considering the maneuverability, the motor-battery pair can be better than the motor-FC counter part (Toyota can offer the excellent drivability by mainly using the motor-FC pair, though.).
However, a battery pack can become heavy, or a small and light, then it can go up soon.
Then, what is the best FC/battery ratio in order to offer the best drivability and cost-effectiveness?
Nissan e-power (basically range extender) is more frequently battery-driven than Toyota hybrid system (THS):
(cf. 1) Nissan used to try to develop SOFCV (Solid Oxide Fuel Cell Vehicle), however, it was a bit difficult for the frequent start/stop (thus, PEFC, polymer electrolyte fuel cell, is currently used for vehicle electrification.).
(cf. 2) SOFC is used for double/triple-combined power generation. The below is 250-kW SOFC/micro gas turbine double combined power generator:
CO2 emission via thermal power generation in Japan is 400 million ton per year, 30% of the total (1,304 million ton). Triple combined reaches the power generation efficiency of 70% (+20% compared to gas turbine - steam turbine double combined). It can be balanced by using, e.g., SOFC 550 MW , gas turbine 150 MW, and steam turbine 60 MW.
MCFC, Molten-carbonate fuel cell, has already been used for commercial power generation such as combined. It still is a good choice for a relatively large-scale combined power generation.
H2-CO2 Fuel Cell is under research. This produces CH4 that can also be used as fuel.
(cf. 3) SOFC can be also a choice for airplane electrification. NASA and JAXA are conducting the SOFC/micro gas turbine research. Diesel oil or desulfurized jet fuel would be used. Although it is not a perfectly zero-emission vehicle, it is still beneficial for our sustainable society. Much better than daydreaming, at least.
(d) Honda i-MMD-based?
Honda i-MMD IC-HEV is also more frequently battery-driven than THS.
CLALITY Fuel Cell uses a large FC stack (104 kW), though:
Thanks to the SiC, PCU is quite compact-sized.
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