Generator bicycles - #1 stages 1 & 2

The first post in a series of posts on the different bicycles and their stages.

Bicycle #1 stage 1 was based on a BH Fitness ZTX exercise bike:
- removed the plastic covers, electrics that controlled the settings and the display,
- also removed the magnet to make sure that that doesn't cause any resistance
- 120W electric motor from ebay (24V, 3500 rpm, 66% efficient)
- very important to have a saddle you like: Brooks B66 saddle (http://www.brookssaddles.com/en/Shop_ProductPage.aspx?cat=saddles+-+city+%26+heavy+duty&prod=B66)
- 80-90 revs gives approx 24V, the MPPT solar charger converts that to 5A @ 14V
- i'd prefer 60-70 revs, so 80-90 is hard work
- the motor would get quite hot after a couple of minutes so had to put a 0.84W, 12V fan on it
- to drive the motor i attached a wooden disk to the flywheel and screwed on a gear from one of my old bread making machines
- the belt from the bread machine also fitted the motor!
- not sure how long the plastic gear and tiny belt will last, have one more spare bread machine...

The combination of the high revs and the low energy output got me thinking of what i had to change.


So on to stage 2 with a new motor: 240W electric motor (MY1016, 24V, 2650 rpm, 75% efficient). The larger motor uses a different gear so i couldn't just swap the motors over. So got a new belt which ran directly on the flywheel, the benefit was a much better ratio. So finally more power at lower revs!

But it didn't work out that way: the belt was on pretty tight but still slipping a little bit, so after a couple of minutes the belt got warmer and larger and started slipping a lot. Makes sense: the outside of flywheel is a flat copper strip.

So i switched back to the first stage motor and built bicycle #2.


Status: no longer operational even though the gear and belt survived of stage 1 survived!

A couple of images of the bicycle in stage 2. Also shows the wooden disk with the bolted on gear for the stage 1 motor.

Generator bicycles

First of all a quick post with an answer to the question why?

Because it's a fun project!

And secondly it's good excuse to put in an hour of exercise a day!

Electricity usage

The third post in this series is about what i use the electricity i generate for, in short i use it to run two computers, most of my lights and some ventilators.


I've got two computers running 24 hours a day, both run on extreme low power: 150-250 mA each. That's needs approx 10 Ah a day (@ 12V). They're both headless AMD Geode LX800 500MHz, 256Mb, 16Gb (CF card).


The first one runs Voyage Linux (http://linux.voyage.hk/) and is used for:
- sensor readings from my 1-wire network (temperature, humidity, pressures)
- solar charger info
- my local wiki etc

The second runs Monowall (http://m0n0.ch/)

Lighting:
To reduce the amount of energy required i've replace the living room lights with 2x 480 led lightstrip (5 meter each), 1x 120 led lightstrip (1 meter) for general light (don't see the ones i got on ultraleds anymore).

As they're very bright i've added a dimmer (has the additional benefit of reducing power usage) which comes with a remote: http://www.ultraleds.co.uk/ct110rf-dimmer-with-remote-control-p-1999.html. Most of the time i run them at just under 2A @ 12V.

Then i've got a 24 led reading light: 150 mA @ 12V.
And the same as a desk light for the hobby room: 150 mA @ 12V/

Storing electricity

This second post is about storing the electricity that gets generated.

I'm using a 125VA lead acid battery to store the energy.

To make sure the battery is properly charged i'm using a Morningstar Sunsaver MPPT (http://www.morningstarcorp.com/en/sunsavermppt).
- the best feature is that it adjusts the voltage to the appropriate level, that is necessary as the solar panels go up to 17V and the generator bicycle up to 36V. A battery wouldn't like voltages like that and simply disconnecting when the voltage is too high would be a waste of energy.
- i've hooked up a http://www.morningstarcorp.com/en/pc-meterbus-adapter to have a detailed log of how much energy went in and out,
- the MMPT also switched of the power to the load if the battery voltage gets too low. That came in handy when my old battery died after three years (at the end it needed a twenty hour charge to keep going for four hours at 500 mA).

Generating electricity

The first in a series of posts about green energy, this is about the different ways i generate electricity at home:

1. solar panels (http://www.sunshinesolar.co.uk/):
- covers basic electricity usage (well, some of the usage, i'll go into that in a later post) from March to September (as long as the sun shines a bit, mainly an issue in March-April and September).
- total of 200W, placed on the inside, half facing east, half facing west,

2. generator bicycle
- for when the sun doesn't shine (enough), more info in a later post.

3. and finally a 18V power supply
- for when there is not enough sun/i didn't use the generator bicycle enough...

my first blog post!

Creating a blog is easy: go to www.blogger.com and within a couple of minutes you're all set with your brand new blog. Which is completely empty... no posts, no followers, nothing.

Time to do something about that!