forums energies: society, ecology and clean technologies

Hi everyone, I'm new here, so I introduce myself:
My name is Thomas and currently I am in Vietnam (in Hanoi) for 1 month.

I left with an association of medical students who take care of helping some families who live in a slum on houses / boats on the banks of the Red River.
When I learned that I was in ange school (even if it only started for me), they all fell on me and asked me if it would be possible either:

- Of run a fan using energy from the river (there are a lot of young children who live in this slum and a priori a small fan that would not be luxury)

- either recharge a battery (it's too expensive for these people to charge them in town)

The big problem is that here the budget is very very small (I could almost say that there is none).
I do not yet know the flow of the river, but I will try to use the plug technique (seen on another subject) and estimate the surface.

I have some rough ideas but really nothing concrete yet.

given my budget, I first thought of a small system water mill with a reducer (bicycle recovery) and finally a dynamo (again the bicycle)
If I'm not mistaken, a bicycle dynamo delivers 6V to 0.5A continuously?
Is it enough to charge a battery or run a fan? ( for the fan an AC alternating current would be better, right? lol) in any case with a dynamo I would not have a problem with the speed of rotation ...
Maybe several mills in parallel to increase the intensity?

Otherwise the great passion of the Vietnamese is the "motorbike"!
it might be possible to get an alternator on a scooter in the area ... but I imagine that the speed of rotation for a good operation is too high for me ...

Small precision, basically I'm not a DIY ... but hey I must be able to find it in the corner


Do you think it's utopian as a project where there might be a way to achieve something?

Thank you for your answers !
++

For the bicycle dynamo, that's roughly it: it's enough to power 2 bulbs. To know the rotational speed, given that the dynamo takes its movement on the rim, you can calculate it by knowing the assumed speed of the bike, the perimeter of the wheel and the perimeter of the wheel of the dynamo.

I could see a paddle mill made up of two bicycle wheels, connected by blades

If you need 12 volts, no need to try to put the dynamos in series: it is not continuous. Batteries must be charged separately, then put in series.
Attention, you must straighten to connect to the batteries.

Maybe you can get some ideas with Christophe's post on the washing machine drum as a paddle wheel: https://www.econologie.com/forums/tambour-de ... t6303.html

That, you will always find raw material and "crafts" to help you do it.

I actually think when in the case of a river and a developing country, the solution of the float-mounted recovery washing machine is the most suitable.

Now my "DIY" is not yet finished. Otherwise you have this too: https://www.econologie.com/forums/une-micro- ... t6495.html (the idea is the same as that of the machine drum wheel but the means are different)

A Canadian aquatic version well could cool the air more efficiently.
If there are waves, it can also be used as a bellows.

bebeours wrote:A Canadian aquatic version well could cool the air more efficiently.
If there are waves, it can also be used as a bellows.

It is true that it is a very good idea.
In addition, this would have the advantage of dispensing with the double transformation of mechanical energy -> electrical energy -> mechanical energy implied by a dynamo and fans.

Indeed, the start of the "well" could consist of a buoy which would support a system of paddle wheels mechanically turning (chains, pinions, gears, ...) a fan which would push the air into the "well" .

Targol wrote:It is true that it is a very good idea.

I had a great idea! I had a great idea! I had a great idea! I had a great idea! I had a great idea!

As for sending the air into the pipe, I was thinking of a simplified oscillating column system or
a bellows fed by the difference in wave heights between two points.
Or, if it is to use the current, a crank and piston system. As in our old forges powered by animal force. A turbine directly connected to the paddle wheel could also simplify the system.

Or, a buoy that would turn on itself and send the air into the pipe.
Or ...

If it is just for a ventillo then the best are solar panels connected directly!

There is sun, it heats up and it turns ... there is none that does not wear out! Yapaplusimple!

Christophe wrote:If it is just for a ventillo then the best are solar panels connected directly!

There is sun, it heats up and it turns ... there is none that does not wear out! Yapaplusimple!

Yes, except that in the initial specifications proposed by TomTom, there is the fact that it should cost nothing (or almost). The PV falls out of this category.

It's true, but there is nothing that costs nothing ... a paddle wheel, even a waste one, will have a cost!

But it is true that the PV is still the most expensive ...