A Wierd Idea

[neptune]

I had an idea today .Not sure if it has been mentioned before . Imagine you have a very small petrol powered generator mounted on your carrier . Now you have two 36 volt 1 amp hour batteries . One is connected to the bike to power it . The other is being charged by the generator . These batteries are then changed over at whatever periodicity you like , by an electronic circuit . The engine is not being used to propel the bike , so the machine is not a moped . The engine can be powered by any fuel , including agricultural diesel . Instead of batteries you could use Ultra capacitors of the type used in some fast-charge power tools . So what we have is a moped without road tax , insurance or license requirements . OK I know we ride electric bikes to get away from noise and fumes . So its just an idea . Any Comments please ?

 

[steveindenmark]

I can see what you are saying.

The first problem is finding a "very small" petrol engine. That is going to be difficult.

My second thought, and this is just a personal one, is that I use an electric bike instead of using a moped. This is in order to help save the enviroment. Strapping on a petrol engine would put me back at square 1.

Steve

 

[flecc]

Certainly legal as far as e-bike legislation is concerned, but there are other legal issues. There is obscure law about manufacturing being banned on public roads, and this is making electricity. For example, there was an early period when the first "readymix" concrete trucks hit the roads when they were illegal. There's also some pollution legislation which might apply, depending on how that has been drafted.

Meanwhile, here's an illegal e-bike, Panasonic crank motored Giant Lafree with a second front hub Heinzmann motor and a tiny petrol generator on the carrier. It can run on the 24 volt battery feeding either motor, or with the generator running with both motors together:

 

[rog_london]

I'm not sure that's the point!

I also can see what is being said - it's an interesting legal conundrum, and the technicalities matter little. I won't dwell on the 'saving the environment' thing.

I suspect it's already covered in law somewhere - if it were not, there would be nothing to prevent you doing something similar with a car - and then two batteries plus an engine running on duty-free fuel would be a much easier proposition from a technical standpoint.

Probably the law on an 'electric' vehicle requires the power to be derived externally. That's the crucial difference - it might well be that the current you use to charge the battery on your bike already comes from an engine somewhere else. That's fine, but if you're carrying the engine and its fuel supply 'on board' it's a different matter.

A normal (car) diesel will run happily on domestic heating oil, or of course 'green' agricultural diesel oil.

Rog.

 

[neptune]

From the Giant picture it looks as if small generators are available off the shelf . I reckon that even if it now legal , new laws would be passed very soon if it caught on . Incidentally , coming from Lincolnshire , agricultural "duty free " diesel is red in colour in the UK but green in the Republic of Ireland . Whilst electric bikes are "greener " than cars , they are not whiter than white . In effect most Ebikes are either coal powered or worse still atomic powered . The reason I like electric bikes is that they are almost silent and free of fumes . I also do 10 miles a day on my normal bike . All I am saying is that we must not feel "holier than thou " .

 

[Deleted member 4366]

I suspect it's already covered in law somewhere - if it were not, there would be nothing to prevent you doing something similar with a car - and then two batteries plus an engine running on duty-free fuel would be a much easier proposition from a technical standpoint.

Probably the law on an 'electric' vehicle requires the power to be derived externally. That's the crucial difference - it might well be that the current you use to charge the battery on your bike already comes from an engine somewhere else. That's fine, but if you're carrying the engine and its fuel supply 'on board' it's a different matter.

What if the generator's towed in a trailer charging the battery there - ready for a quick change=over.

 

[rog_london]

Ah - I knew about the red/green thing - just forgot about it. I should have remembered because my dad used to run a small sailing boat with a diesel engine.

I was thinking a bit more about the engine and two batteries set up - I suppose then you'd still have a 'hybrid' vehicle in law. It's as well to remember that it's very easy indeed to step over the line and then your e-bike becomes a 'motor vehicle'.

Tiny generators are indeed available off the shelf. You don't very often see them in Europe I suppose.

Rog.

 

[flecc]

I suspect it's already covered in law somewhere - if it were not, there would be nothing to prevent you doing something similar with a car - and then two batteries plus an engine running on duty-free fuel would be a much easier proposition from a technical standpoint.

Probably the law on an 'electric' vehicle requires the power to be derived externally.

There is nothing in the EN15194 technical specification, the 2002/24/EC or 1983 EAPC regulations which excludes having a generator charging a separate and unconnected battery. The crucial thing would be that one would have to replace the battery in use manually, taking it's place, not just switched into circuit from a differently mounted position.

The technical position for cars may be different, but pre-charged battery swapping for e-cars is considered legal.

 

[Orraman]

Posted 19 Sept 2011

Ref. photo in post # 2.

Some years ago I spoke to a chap in the DOT about the idea of using a generator in a trailer to alternatively charge and swop 2 smaller batteries. Two batteries charged in the trailer he said would be acceptable but two motors would be illegal.

Later in the conversation he agreed the 2 batteries could be swapped electrically by a relay. But when I queried the possibility of using 2 independent capacitors with electronic switching instead of batteries he was sure that would not be allowed but couldn't say why.

Nice chap, tried to be informative and helpful.

Dave

 

[flecc]

While the relayed battery swapping would be legal on a pure e-bike, it almost certainly wouldn't be if a generator charged the second battery, since that would make it too close to being a hybrid petrol/electric vehicle.