Would you go electric?

Hi Guys,

I'm a new member here, hoping that you could all lend me a hand. I'm a final year uni student at Coventry studying Automotive Design. I worked at Land Rover for 6 months over the summer and loved it. My family are total 4x4 nuts and we own and race god knows how many Land Rovers.  

Basically for my final year project I am designing (and building a 1/4 scale model) a 4x4 capable of running in the Baja and Dakar rallies and then being hosed down and used on the shopping run. Sound bland but there are many little innovations and cool features to it, but i will fill you in on those at a later date.

I'm currently trying to work out my means of propulsion. Originally i was going to use a full 4x4 hybrid system using batteries, an electric motor and a small but powerful V4 engine. The use of an engine was due to my fears about torque needed for 4x4's but after doing some motor predictions for my minor project I realized that I could produce the amount of torque needed using electric motors. This would work out as a much greener and cheaper form of propulsion whilst providing a much higher MPG.

My question to you guys, as frequent users of off road vehicles, what propulsion would you choose if you could get the same performance across the board for both range and torque?

Any information you guys could give me would be great. This is just a really informal survey at the moment but I may conduct a more professional one in the near future.

Thanks guys,
Really appreciate any help,
Sorry for the lengthy intro,  

Orpheus  

I think electric would work but I would suggest that you take it one step further and use concept that they plan with chevy volt (and a concept long ignored) A electric vehicle with a small backup engine that can charge batteries and extend range. It does not have to be a big one as 6 or 8 KW work work fine as it is meant to extend discharge time or recharge when sitting. You could even use a propane powered generator as they make them in that power range and it would be greener than gas and no worry about fuel spill of feed on of angle operation. Also easier to fit tank to it and refuel/switch tanks on trail is need be. A 20 lb or forklift bottle could run generator all day and then some. You could also reduce size and weight of battery pack because you would be able to supplement it if need be.  

That sounds like a great idea. Could you recommend a CNG generator? I have been looking on the web and have no idea what I am looking for...  

I will be sure you get a mention in my research report  

Thanks

Orpheus  

Generac markets propane powered generators under the America name. They make the APG3535 (3.5 KW peak) and APG3560 (6 KW). JD Tek  makes the JD6500 (6.5KW). I do think that the APG3535 would be a good choice as it is small and quiet and very efficient on fuel. You could even use two of them for back since they weigh about 100 lbs each and chances of both failing at once would be nill and it would let you bring on aux charge power in stages too (just a thought) There are others out there but I wanted to name a few for you.  

Thats awesome Snoman, thank so much for all your help.

Just one last question, could you replace a Propane tank with CNG?

Thanks again  

GNG requires different jetting (higher flow rate) Plus CNG was much more limited storage capacity for mobile usage as it requires large heavy tanks to be stored under high pressure in a gas state. Propane liquefies easily at ambient temps so it can be stored in a far denser state. This means you need about 65% more storage space volume and high pressures to store same amount of energy as in propane. The net result is that CNG tanks and gas weighs more than propane tank and fuel in it too. Propane is a liquid at about 150 PSI at room temperature and rarely exceeds 300 PSI even when hot. CNG requires pressures exceeding 1500 PSI to get any usable range which means heavier tanks. The biggest draw back of CNG as a motor fuel is storage and range.