CitiBikeNYC Dead Batteries

The batteries are dying. Today I saw a CitiBike van driving around swapping out the batteries in a few dead kiosks in my neighborhood. They use normal 12 volt lead acid batteries, like a big car battery but deigned to be more deeply discharged (sometimes called “marine” because you use them on boats).

Once a kiosk battery is dead, you can’t get or return bikes there. Particularly problematic is that when you try to dock a bike in a dead kiosk, it feels like it locked in- but if you pull hard enough it will come out again.

If you leave your bike is a dead kiosk, best case is that you will not be able to get another bike without calling the 800 number to reset your account. Worst case it that someone will take the bike and it will be a big hassle.

Always wait for a light after you dock a bike. If you don’t see a light, pull really hard on the bike to pull it out and then try another dock or even another kiosk.

I can’t believe that this is how the system is designed to work, so either New York streets are darker than expected (so not enough juice is coming from the solar stalk), or the kiosks are getting much more use than expected (using lots of power), or both.

CitiBike should act fast to solve this problem because goodwill is eroding fast. The system needs to be perceived as reliable to fulfill its goal of being a utility. Once you hit a tipping point where people give up, it is very hard to get them back. We are close to that point.

In the very short term (days), this could just mean raiding every Sears in the tri-state area for deep cycle batteries and wiring 2 or 3 or 4 of them in parallel in each kiosk. There is plenty of room in the box, and this could stretch the operating time long enough that the station would stay up continuously between swap visits.

Distributed systems are usually faster to deploy than centralized ones, so CitiBike could also start deputize local shops or residents to be responsible for swapping and charging the batteries in their nearby stations every day. The total capital investment should be less than $200 per station for a charger. They would have to trust these new deputies with the key to the kiosk cabinet, but dire times call for dire measures. If they cooperated with someone like RPA , I bet they could get this up and running on the worst stations in the next few days.  All it would take is one phone call and key/battery drop to me and all the problem stations in Fidi would be covered (I already have a charger).

Longer term, the station either needs to make more power or use less.

Adding more solar panels could help make more power and I have had especially good results with some of the amazingly cheap and efficient crystalline arrays you can get now on Amazon. These can generate power even in indirect light and adding a couple on the top of the solar stalk could be enough to make some marginal stations stay up continuously.

My guess is that the screens are the big power users in the station. These should be off unless someone is actually interacting with them, rather than running continuously in “attract mode”.

In the short term, you could solve this problem with just a couple of decals and a few lines of code. The decals would instruct people to press any button on the keypad to begin. The software change would involve having the screen sleep after a few minutes of inactivity, and then wake on any keypress. A little extra work could probably sleep the swipe and PayPass readers too for more power savings.


Slightly longer term solution might be to add a physical blinking “start” button to the kiosk to wake the screen. This would involve drilling a single hole, attaching a pair of wires, and sticking on a decal. The blinking light is nice because it attracts attention and advertises that the station is live. Hardware cost less than $25 and probably less than 10 min of labor to install.

Or you could get rid of the screen altogether and replace it with a sign that says “Goto or call 888-RENT-BIKE to rent a bike!”. Heck, put a sticker with the address/number on every dock and now people don’t even need to goto the kiosk at all. Multiple people can rent from the same station simultaneously rather than waiting on line (or, more, likely walking away) while the poor tourists try to figure out the system . If you did this, the system in the station now does nothing but lock and unlock bikes based on a cellular data connection, so you could probably replace the (power hungry and expensive) embedded computer in the station with an off the shelf cellphone that just had a USB interface board to connect the phone to the docks. Something like this would use so little power that it could run for weeks in the dark off a single battery, and almost certainty be cheaper and easier to source than the current embedded system.

Once you got the price of the control system down to less than $500, you could even start deploying “micro” stations with 3 docks and no kiosk. These could be totally mobile since – a flatbed could drop them  into individual parking spaces in a couple of minutes. Great for testing demand in a potential new location, or  just quick response to filling in gaps in suddenly busy areas. These stations would be so mobile that you could even relocate them daily, and each would have a GPS linked cellular connection to the CitiBike system so they would show up the app the moment they hit the ground.

UPDATE 9/5/2016:

This has been implemented with a physical blinking “start” button!

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