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Ken
02-26-2008, 11:06 AM
Just been looking at some details for the Vectrix Superbike.

Looks modern, futuristic almost and the top speed looks good too at 124mph. The bike has a 60kW, that's about 80HP, engine so initially it all sounds good. But is it?

The battery capacity is is a mere 7.5kW/h and at 124 mph you would need to charge the battery up again after around 16 miles and it would take around two and a half hours to get an 80% charge. At 75 mph the range extends to 41 miles whilst at 25 mph with a soft breeze in your hair and huddled over the tank a mileage of 124 miles is anticipated.

The Vectrix range of scooters is better where for a 60 mph top speed a range of 60+ miles is available so for short local trips to the shops we have a reasonable proposition. However the price of 7000 ($14000) might put most people off.

Looking at leccy vs gas running costs for the Vectrix Superbike, and taking the 41 mile range at 75 mph as an example, we are looking at, roughly, the gas usage of a 1 Ltr car. Assuming 41 mpg at a current cost of 4.86/gallon ($8.90) we can compare the cost to the cost of recharging the 7.5 kW/h battery. Assuming a 70% charging efficiency then an input of 7.5 * 1.43 (reciprocal of 70%) gives a required input of 10.725kW/h. At the current UK cost of around 17p per kW/h we have a cost of 1.83. However using the performance to the max the battery would have to be charged 2 1/2 times at a cost of 4.56 over about a seven and a half hours of charge time to cover the same 41 miles. I guess that, for the dedicated sports rider electric bikes are not yet the way to go.

Other alternatives being explored are Fuel Cells (Hydrogen based), Bio-Ethanol works well but, in the UK, there isn't enough land to produce the necessary crops. Bio-Diesel, again, as for Bio-E the product works well but there is not enough land available to grow the necessary crops.

Ken.

Eric
02-26-2008, 01:24 PM
Just been looking at some details for the Vectrix Superbike.

Looks modern, futuristic almost and the top speed looks good too at 124mph. The bike has a 60kW, that's about 80HP, engine so initially it all sounds good. But is it?

The battery capacity is is a mere 7.5kW/h and at 124 mph you would need to charge the battery up again after around 16 miles and it would take around two and a half hours to get an 80% charge. At 75 mph the range extends to 41 miles whilst at 25 mph with a soft breeze in your hair and huddled over the tank a mileage of 124 miles is anticipated.

The Vectrix range of scooters is better where for a 60 mph top speed a range of 60+ miles is available so for short local trips to the shops we have a reasonable proposition. However the price of 7000 ($14000) might put most people off.

Looking at leccy vs gas running costs for the Vectrix Superbike, and taking the 41 mile range at 75 mph as an example, we are looking at, roughly, the gas usage of a 1 Ltr car. Assuming 41 mpg at a current cost of 4.86/gallon ($8.90) we can compare the cost to the cost of recharging the 7.5 kW/h battery. Assuming a 70% charging efficiency then an input of 7.5 * 1.43 (reciprocal of 70%) gives a required input of 10.725kW/h. At the current UK cost of around 17p per kW/h we have a cost of 1.83. However using the performance to the max the battery would have to be charged 2 1/2 times at a cost of 4.56 over about a seven and a half hours of charge time to cover the same 41 miles. I guess that, for the dedicated sports rider electric bikes are not yet the way to go.

Other alternatives being explored are Fuel Cells (Hydrogen based), Bio-Ethanol works well but, in the UK, there isn't enough land to produce the necessary crops. Bio-Diesel, again, as for Bio-E the product works well but there is not enough land available to grow the necessary crops.

Ken.


It seems to me electricity/fuel cells might make economic and practical sense for an in-city commuter bike where speed/performance are not big issues.

But it's hard to see a viable electric/fuel cell sport bike - by which I mean one that can match the power/performance capability of a modern liter class bike for about the same money....

Ken
02-26-2008, 01:54 PM
It seems to me electricity/fuel cells might make economic and practical sense for an in-city commuter bike where speed/performance are not big issues.

But it's hard to see a viable electric/fuel cell sport bike - by which I mean one that can match the power/performance capability of a modern liter class bike for about the same money....


I agree, for a city commuter the current Vectrix scoots look to give a sensible mileage and a sensible level of performance. It is only the cost that, at the moment, is out of proportion.

Current technology is advancing apace and the current battery developments - Li-Ion, LiPo - are streets ahead of what was available even a couple of years ago. My guess is that we will progress towards Hydrogen Fuel Cell development with, perhaps, small on board gas/bio engine driven generators coupled with regenerative braking to extend the range to more acceptable levels. As battery development progresses electric power will become more viable. A 50kW/hr battery would give superbike perrformance with an un-recharged range of about 100 miles. Add in regenerative braking and, possibly, small back up engine generation and electric power would start to be a goer.

Ken.

Eric
02-27-2008, 07:24 AM
It seems to me electricity/fuel cells might make economic and practical sense for an in-city commuter bike where speed/performance are not big issues.

But it's hard to see a viable electric/fuel cell sport bike - by which I mean one that can match the power/performance capability of a modern liter class bike for about the same money....


I agree, for a city commuter the current Vectrix scoots look to give a sensible mileage and a sensible level of performance. It is only the cost that, at the moment, is out of proportion.

Current technology is advancing apace and the current battery developments - Li-Ion, LiPo - are streets ahead of what was available even a couple of years ago. My guess is that we will progress towards Hydrogen Fuel Cell development with, perhaps, small on board gas/bio engine driven generators coupled with regenerative braking to extend the range to more acceptable levels. As battery development progresses electric power will become more viable. A 50kW/hr battery would give superbike perrformance with an un-recharged range of about 100 miles. Add in regenerative braking and, possibly, small back up engine generation and electric power would start to be a goer.

Ken.


This hydrogen business is curious... by which I mean the actual operative side (the machine) is quite capable - however, the fuel side is another matter. It takes a great deal of energy to free hydrogen from water, etc. - and as I understand it, it's a "net loser" in that respect. There are also significant technical obstacles to be dealt with insofar as as infrastructure (refueling/distribution).

It may work, eventually - but we have a long road ahead of us...

Ken
02-27-2008, 03:34 PM
This hydrogen business is curious... by which I mean the actual operative side (the machine) is quite capable - however, the fuel side is another matter. It takes a great deal of energy to free hydrogen from water, etc. - and as I understand it, it's a "net loser" in that respect. There are also significant technical obstacles to be dealt with insofar as as infrastructure (refueling/distribution).

It may work, eventually - but we have a long road ahead of us...


From what I have seen there are many ways of producing Hydrogen. Some are currently available but not very efficient. Some are efficient in theory but not yet proven. To me it looks like Generation IV nuclear reactors which can switch between High Temperature Electrolysis (HTE) generation of Hydrogen at night, when electrical demand is low, and generation of electricity during the day could provide commercially viable processes. However they will not be on line until the 2030s so do not hold your breath, especially as the process is, as yet, not fully proven.

Ken.

Eric
02-28-2008, 06:43 AM
This hydrogen business is curious... by which I mean the actual operative side (the machine) is quite capable - however, the fuel side is another matter. It takes a great deal of energy to free hydrogen from water, etc. - and as I understand it, it's a "net loser" in that respect. There are also significant technical obstacles to be dealt with insofar as as infrastructure (refueling/distribution).

It may work, eventually - but we have a long road ahead of us...


From what I have seen there are many ways of producing Hydrogen. Some are currently available but not very efficient. Some are efficient in theory but not yet proven. To me it looks like Generation IV nuclear reactors which can switch between High Temperature Electrolysis (HTE) generation of Hydrogen at night, when electrical demand is low, and generation of electricity during the day could provide commercially viable processes. However they will not be on line until the 2030s so do not hold your breath, especially as the process is, as yet, not fully proven.

Ken.


2030s... yep. That is a long way off, indeed.

We may reach a crisis point with energy/oil production long before then.