Automotive X-Prize

[Mark Parsons]

Anyone want to take a run at getting $10 million for presenting a car that gets 100 MPG?

http://www.cbc.ca/technology/story/2007/04/02/auto-prize.html

The guidelines specify that the car must be appealing to buyers and easy to mass produce — warning that concept cars or "science projects" won't qualify.

The contest will require vehicles to meet tough emission requirements and get 100 miles per U.S. gallon (about 42 kilometres a litre).

Gasoline: US gallon = 115,000 Btu = 121 MJ = 32 MJ/liter = 8.9 kWh / liter

So - 42km on 8.9kWh or less wins provided tough emissions requirements are met.

Tesla Roadster uses 110Wh per km. 42km * 110Wh = 4.6kWh. Therefore Tesla Roadster can win this x-prize by getting 50% of gasoline's BTU's converted into electrical energy. http://www.teslamotors.com/learn_more/energy_efficiency.php

Any ideas on how to convert the BTU's into electrical kW's with over 50% efficiency? Or just state that a gasoline burning co-generating multiple recovery cycles electrical power plant with about 60% (these plants exist today) thermal to electrical efficiency is providing the power that charged the Tesla's batteries and claim the prize now.

Seems too easy...

[Joe Blake]

"Appealing to buyers and easy to mass produce"???

Aye, there's the rub.

I think it's easy to produce a fuel efficient vehicle - hard to sell to the public.

But, good luck to whoever.

Joe

[George Craft]

I commute 100km per day with a 3 cylinder 5 speed Geo Metro. I believe that I am getting 50 mpg even when driving at 120 km/h.

I was wondering what would happen if I took this lightweight car and fitted it with one of these revolutionary engines such as the diesel one listed below?
http://www.regtech.com/rotaryprinciple.html
If what this company is advertising is really true, then this should solve the problem. I believe that the problem can be solved but at what cost?

If a few school kids can make an amazing 300 hp, 50 mpg biodiesel car that will outperform most production vehicles on the market, then who knows what they can create?
http://www.autoauditorium.com/TdS_Reports_2005/photos_007.html

[Mark Parsons]

Welcome George,

Living in Calgary - current home of Canada's cheapest gasoline - and driving a high fuel economy vehicle anyway. Well relatively cheap gas, eh? :rolleyes: These days there is no such thing as cheap gas anywhere and its only going to continue in 1 direction.:eek:

I found your link to regtech interesting. Appears to be yet another variation of the swash plate motor. In this case using vanes instead of pistons. Does not appear that they have even made a prototype.
http://en.wikipedia.org/wiki/Swashplate_engine

I'm a firm believer that a signficiantly more efficient engine than the reciprocating internal combustion engine can be produced and popularized where a range beyond pure electric storage is required.

How about a direct linear combustion electromagnetic engine?
http://peswiki.com/index.php/Directory:Linear_Combustion_Electromagnetic_Engine s

Regards,
Mark

[George Craft]

Thanks for the link on linear electromagnetic combustion engines, Mark. I haven't seen this one before and would like to attempt such an engine. I have recently got an interest in forging my own parts. I purchased all of the books from http://stephenchastain.com/book1.htm and plan on building a few of these revolutionary new engines.
Most of the manufacturers of these engines are sitting on their hands and I have seen very little real progress. As long as I have an understanding of how it works, then I will give it an attempt at making it work. The linear electromagnetic motor looks like it can also be done using the stirling engine principle. This would be the ultimate use of a stirling engine. Just think about it. Every time the sun came out, a linear electromagnetic stirling engine could be topping up your batteries with sun power. Not a bad deal at all...
http://peswiki.com/index.php/Directory:Linear_Combustion_Electromagnetic_Engine s

[Mark Parsons]

Hi George,

I spent about 10 years in the die casting and foundry industry and have no desire to return even if on a hobby basis. I will stick with mill and lathe hand work when metal shaping is required. Since my background is electrical this aspect is plenty challenging.

Since you raise the Stirling engine from solar source idea - I stumbled across this New Zealand company a couple of years ago. http://www.globalcooling.nl/howitworks.html
Their free piston moving magnet product is supposed to be very close to fully reversible - i.e. - put heat or cool in and get electricity out OR put electricity in and get heat or cooling out. They are chasing the cooling marketplace with a higher efficiency product than current heat pump technology. It seems to me this product would make for nice modular solar based stirling generators. Perhaps using Fresnel lenses or reflective type concentrators onto the heat acceptor node.

Regards,
Mark

[George Craft]

I had a thought the other night about how to make an engine efficient. This thought was fairly bizarre.

The idea was to take a turbine engine that expels its exhaust into a vortex tube which uses its hot air from one end and cold air from the other end, to run a stirling engine. It seems like a round about way of converting energy but I wonder... Would this be efficient or would all of the losses add up and make the effort futile?

References:
http://www.airtxinternational.com/how_vortex_tubes_work.php
http://en.wikipedia.org/wiki/Stirling_engine

[Mark Parsons]

Interesting...:)

I know a combined cycle gas turbine with co-generation of exhaust gases can reach BTU to Watt efficiencies over 60%.

Even after the second stage steam turbine co-generation the depleted gas turbine exhaust gases are plentiful in volume and still relatively hot - about 300F.

Vortex tubes are not very efficient at producing just cold btu's, but I would expect that combined hot and cold btu's must be fairly efficient - after all there is no moving parts for friction to rob power.

I don't know what pressure the depleted exhaust gas is at. The vortex tube is powered by the pressure differential to atmospheric. Combustion products may also 'gum up' the vortex tube rendering it a maintenance headache. A very clean burning fuel gas would be required. This is why natural gas is normally the only co-generating fuel used. The cold side of the vortex tube would still need to be well above 32F or the water combustion product would freeze out and stop the vortex operation.

The Stirling engine may be a good 3rd stage complement and possibly a good 2nd stage co-generator in place of the steam boiler and low pressure steam turbine.

I would love to hear from a Power Generation Engineer about whether a 3rd stage of power harvest is economically viable. Might be hitting the diminishing returns button. BTU's to Watts - 1st stage - gas turbine - 45% efficient, 2nd stage - low pressure steam turbine adds another - 20%, 3rd stage - vortex tube to stirling engine adds another - 10%???. 2nd Law of Thermodynamics is the constraint. Even 3 very efficient alternators alone will rob 6% of 45% + 6% of 20% + 6% of 10% = 4.5% of the total.

Interesting speculations :cool: