Charging bicycle light batteries can be a pain, so wouldn’t it be great if you could ditch the batteries completely? Well Danish company Reelight has launched a battery-free cycle light on Kickstarter that pumps out up to 118 lumens and is totally frictionless.
Reelight has been working on the concept of a bicycle light powered by nothing more than the rotating wheels in your bicycle. Way back in 2010 road.cc reviewed a product that used a system of magnets to power the lights, but it wasn’t without its problems.
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For this latest design, Reelights has developed a product that makes no contact with the wheel rim. Reelight says it has developed a patent pending technology that “takes advantage of Eddy currents ( loops of electric current induced within conductors by a changing magnetic field in the conductor) generated by the rotation of the bike’s aluminium rim,” so there’s no speed-robbing friction.
Reelights has developed a generator which uses the magnetic field of the Eddy currents to propel six neodymium magnets, which supplies the LED with power. The design produces sufficient power to run to 1W LED lights. It has tuned the beam, with a concentrated front light beam and an extra wide angle rear light.
What happens when stop pedalling though, say pulling up to some traffic lights? Reelights has thought of that, and each light has a backup system which supplies low power LEDs to maintain visibility to other road users.
According to the company, the light, which are a fully integrated design, can be fitted easily to most bicycles in under 30 seconds with no tools needed, other than an Allen tool to make use of the anti-theft protection.
The Reelight Neo is currently on Kickstarter where the company is hoping to raise $60,000 of funding. At the time of writing, it has surpassed the halfway point with 33 days to go. To get your hands on a light will cost just $18, with a choice of colours to choose from. That’s 70% off the estimated $60 RRP when the lights go into full production.
Check it out at www.kickstarter.com/projects/1651132789/neo-worlds-most-powerful-friction-free-bikelight
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10 thoughts on “Battery-free Reelight bicycle light launches on Kickstarter”
Can’t help thinking these
Can’t help thinking these lights are not positioned in the best place, fork and seat stay?, they’re going to get covered in road crap and are obscured by the wheels/ fork/seat stay from one side. Bars and seatpost/rear rack/mudguard have got to be a more visable option.
Also, “To get your hands on a set of lights will cost just $18, with a choice of colours to choose from. That’s 70% of the estimated $60 RRP when the lights go into full production.”?
70% of 60 is 42 by my reckoning, or is “70% of” supposed to be “70% off”?
“so there’s no speed-robbing
“so there’s no speed-robbing friction.”
Big physics red flag here: there may be no parts in contact with the wheel, but since the light is taking energy out of the system to charge itself, there is (and must be) drag. In this case, that will manifest as the eddy currents causing their own small magnetic fields which repel the magnet in the light, causing you to have to work a little harder to push the wheel around.
If there was no additional drag at all, this would be a free energy device, and in this house we obey the laws of thermodynamics.
rkemb wrote:
You are right that the amount of energy put in the system has to be the same as the amount of energy out of the system. But it is considered that a man can produce about 100W on a bike and since a small LED-light not even produces 1W of power, you won’t feel the difference when the LED-light is working or not. That’s why they say that there is no speed-robbing friction (hence: there is friction but you won’t feel it).
Because there is no mechanical friction, this type of technology is considered more efficiently. Only when you would attach bigger powers (about 5W or higher), you would start to feel the ‘magnetic’ friction.
£18 isn’t for a set of lights
£18 isn’t for a set of lights, it’s for ONE light.
The way they’re using kickstarter seems a little odd as well, the estimated shipping date is Decemeber 2015, when it’s running until Dec 8th. Clearly if they’re shipping in December they’ve already made them and you’re just buying a light rather than funding production.
Quote:
Yes, raised my physics red flag too – but.. the loses in the system will not be from friction. This design sounds like it will be a very effecient transfer of power – so while energy will be taken out of the wheel (so you will need to pedal a tiny bit harder), the friction losses associated with a traditional dyno will not be present… so a more efficient system, and will be interesting to hear how noticable the extra pedelling effort is.
I thought I’d give a set a
I thought I’d give a set a try for £30 inc delivery. I do like a gadget/light. Not going to work with my carbon rims though ;-). I’ll have these as emergency/supplementary lights on the commuting bike.
I went for another Kickstarter light the DING as well earlier this year.
https://www.kickstarter.com/projects/dingbikelight/ding-bike-lights
Looks like that one won’t now turn up till December now but they have made some good improvements on the original design.
These are a copy of the
These are a copy of the Magnic lights which have been around for a few years (the latest version is very good). Be interesting to see how these new units compare and whether the patents already filed for this cause Reelight any problems – having seen the patent, I’m skeptical they can get around it but time wil tell.
Although contactless, there is drag from these systems – it’s just so small as to not be noticeable. I haven’t been able to measure any slowdown of the wheel during coastdowns with and without the lights. LEDs are so efficient now that running 1W lights only needs ~3W of power input. I certainly can’t tell the difference while riding. The output is fine for being seen by (particularly at the back) and just about good enough to light the way on well lit roads but you need something beefier for unlit areas.
Biggest issue is mounting – they have to be VERY close to the rim to work (within a few mm), so unless the mounting system is very stiff, the average British road can cause them to bounce against the rim a lot over bumps. Magnic had to redesign theirs to get them to work robustly (which they do).
Visibility from certain angles isn’t brilliant because the wheels block some of the light – best solution for me is to use 2xfront and 2xrear which with the Magnics gives great all round visibility. It also makes the bike look more like a moped from a distance – I’ve noticed a significant drop in the amount of tailgating & close passes on evening rides along country roads with them.
“Not going to work with my
“Not going to work with my carbon rims though ;-).”
Graphite is conductive, and so is CF, although I don’t know if there would be enough network connectivity between the fibres to get significant eddy currents building up. Would be interesting to try it with something like this.
Battery or hub dynamo light
Battery or hub dynamo light as Rim dynamo is no go. Just not as efficent
Looking at the RRP in the
Looking at the RRP in the kickstarter campaign ($60) for one light?!
So when they come to production they’re going to cost $120 for the set (£80)!
I don’t think so!!!