Stirling engine generator charges 12-volt batteries!

I'm finally able to show in this video that my cheap little water bottle Stirling engine can charge 12-volt batteries! This opens up a whole new world of applications for it, whether 12-volt lights, pumps, fans or even 120 volt devices by means of a small inverter. Keep in mind that the engine can run on whatever source of heat is sufficient to drive the engine, including wood, charcoal, alcohol, rice husks, solar energy, and so on.

Note how the current flow goes from negative to positive as the little electric motor changes from starter motor to generator, and then back after the flame is put out. You can also see the battery voltage drop initially until the generator kicks in and then it climbs steadily until the flame is put out and the speed drops. The batteries are two 12V 7AH sealed units from old UPS systems.

This has been a real milestone in the development of this engine and I'm pretty pleased about it. Very fun stuff!!

Category:

Science & Technology

Tags:

• Stirling
• engine
• hot
• air
• motor
• home
• built
• casero
• heat
• thermal
• energy
• sustainable
• development
• appropriate
• technology
• AT
• charge
• 12
• volt
• battery
• generator
• electric
• start
• measurement

[CPD0123a]

Well, we know who's ready for the Zombie apocolips. Between this and the wood-gasifier jet burner, you should be good to go for, well, how long? lol.

So, this can charge small 12v bateries, but I'm guessing it's not powerful enough to charge the big boy 12v car batteries. (Well, unless you get a car alternator and the big car wires, but that might be too much torque to pull off)

[approtechie]

@CPD0123a Bring on the Zombies, LOL! You're right, this is too small to really charge a large 12 volt battery but a bigger engine is in the works.

[makerj101]

What is the dimensions of the water bottle? I guess the reason I don't get much power out of my stirling engine is because I only use a tuna can and you use a water bottle that is much bigger?

[approtechie]

@makerj101 the water bottles are just standard off-the-shelf ones, about 2.75" diameter and I chop them off at about 5.5" long.

[SCENARIOBABY]

dont forget wood gas flame, biogas flame! I want to see a diy vid by you approtechie! We can learn alot from you. Peace and blessings

[approtechie]

@SCENARIOBABY Just posted the engine running on wood gas from a coffee can gasifier wood stove I built.

[CPD0123a]

@approtechie Oh dear...

[approtechie]

@makerj101 the stainless steel water bottle allows me to get a significant temperature difference going, I use fine stainless steel wool for the displacer, 1/3 of the bottle is for cooling, it's a beta version which allows the diaphragm to dip down into the same volume used by the displacer, I use ball bearings on the crank, and otherwise reduce friction as much as possible, I work on balancing the crank as best I can, long conn rods for minimal side forces, and attention to detail. And luck!

[makerj101]

Wow that engine cranks out 2.05 watts! Great job! That's why more then any of my engines can do. The most I've gotten out of mine is 0.02 watts. Only enough to power a few LEDs. How do you make it so powerful?

[approtechie]

@yellowmetalcyborg Yes, I've been corresponding with him. I understand his pumps well and have built air-lift pumps myself. His particular version uses a combination trompe, which compresses air using falling water, and an air-lift pump, which uses said compressed air to lift water to a greater height. I don't really think the Stirling engine is all that suited for use with it, but I sure appreciate the suggestion. Thanks!

[yellowmetalcyborg]

@approtechie Have you seen gaiatechnician's videos on water pumps driven by compressed air? I think combining his ideas with a stirling engine, some pipes and some one way valves would make a truly remarkable water pump. Using expanded air from a stirling engine to bubble air into a long, tall, and narrow tube looks like something worth trying out. His videos are a little difficult to understand, but when there's a will, there's a way.