Hi guys! I wanted to make a device that could send info about windspeed in a dam, where there is no cellphone signal nor wifi. I was wondering if its feasible, and if i can find a technology that could work this out (maybe radio waves? Is it ok if there are no radios near to use them for sending windspeed info to an arduino far away? Or maybe walkie talkie signaling? I dont know if any arduino module use those frequencies)
I was also wondering how to build the wind sensor, id do a very sensible turbine that spins at the slightest wind. Anyone has ideas how this could be achieved? Thanks for helping me in my creation process.
LoRa. Very long range and very low power. But you need a good base station which is in range, but that can be 10Km+. Where is the damn? Check The Things Network for example.
If ground based radio is to be used, none can say if its possible without knowing where this dam is and the type of surrounding terrain, even LoRa has its limits.
So give us a 3D map (i.e, we need to see the hills) of where this dam is.
Here's a picture my friends. It sounds a bit more complicated..
About 50 kilometers separate the dam from where my lab is. Also, there are a lot of hills/small mountains. However, the phone signal is on at maybe half the distance. My idea with what you guys said so far would be to use 2-3 devices passing through the info with long range, then hit an other device with a sim card using cell phone signal. might not be so efficient, and hills seem to be a problem with long range.
The Arduino compatible RockBlock satellite modem works just about anywhere in the world, and is pretty cheap to use if you send only occasional messages.
I was also wondering how to build the wind sensor
Just buy a decent anemometer. They are made to last in bad weather, unlike most DIY attempts.
There are no point to point radio systems that would do that distance in such hilly terrain, unless you used stupid amounts of power.
You would very likley cover that distance with a single LoRa relay on a hilltop near the dam. This would need to be solar powered, the relay would consume circa 20mA continuously.
A LoRa relay is a simple piece of equipment, LoRa device and a Pro mini;
However for ease of maintenance, I would suggest a satellite solution makes a lot more sense.
I dare to say that, in my view, the most complicate thing in this project is to decide where to place the anemometers and how many of them.
I am far for being an wind expert, but the wind near the edge of the dam has more velocity than at its base. I know that because there are horizontal axis wind turbines derived from a classical Savonius rotor, that are placed on the roof of the high towers, near the edge, to benefit from the wind increased speed.
Alternatively, I can think to a sort of calibration of few anemometers.
Another thing I would consider is a simulation (a model) of the wind into the dame starting with collecting data in few other relevant places, where (hopefully) regular mobile networks are available.
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Another, more "fantasy" idea is to measure the curvature of the dam using some tension sensors (easy maintenance). That is to be checked with a structural construction engineer. In fact, the problem is to measure the impact of the wind to the dam, which is a different think than to measure the wind speed (considering the multitude of the factors that go along with the wind and modify the tensions in the dam wall).
As far as transmission is concerned, I would go for intermediate ground points in the wi-fi range (or ground radio range) to the point where mobile networks are available.
I dare to say that, in my view, the most complicate thing in this project is to decide where to place the anemometers and how many of them.
Of course it depends on what exactly one wants to know. A single wind speed meter probably only measures the horizontal velocity vector component of the wind hitting the sensor, but one can draw conclusions from that. If the sensor is 30 cm above the edge of the dam, 50 cm above the water on a floater in the middle of the lake, on the top of the nearest hill, where the sender is, it makes no difference. One probably wants to know the wind direction, too. So if the wind speed is 12 m/s and direction is NNW at the top of the nearest hill, one might be able to draw sufficient conclusions about what the wind is at the edge of the dam, too.
Are you located 50km from the dam and you get cell reception about 25km, so one goal might be to establish a link from your lab to the nearest existing technology ?
I would contact the people running the existing wind generators to see if they have any means already established some way to monitor power or have any existing technology to transmit data.
Also the power generating company at the Dam.
one technology not discussed is the possibility of using a thing called a Land Line or a telephone.
If you can live with a once a day data down load, and emergency updates, you might be able to put in a phone modem and have it dial out once a day under normal data logging, and then also be able to send phone calls when certain conditions exist.
Another option with any sort of mesh network is access from any point on it. similar to a cell phone that can txt by using your new network.
each mountain top tower could have a weather station as well.
wind sensing.
there are quite a few technologies for sensing wind.
the spinning cup anemometer is one. common, simple, cheap to buy.
the Savoius wind generator of which you speak, will output power at speed and although it is not linear to wind speed, feedback would be able to give you some information.
Ultrasonic is a more sensitive way. not sure how easy they are to build. I think they may be expensive to buy.
A vertical axis turbine is a nice and sound way to obtain the energy in insulated places.
Past 10 years the technology progressed very much, so I do not think it is a problem to buy (or even to build) a small wind generator. Only if the wind is very intense, then the turbine design shall be carefully chosen.
Alternatively, long life AGMs or even Li-Ion batteries may do the job as well, providing the transmission is within reasonable limits. My guess is that a visit to the generator/sensor once in a month for maintenance reason is advisable anyway (or can be needed).
JCSB:
Here's a picture my friends. It sounds a bit more complicated..
About 50 kilometers separate the dam from where my lab is. Also, there are a lot of hills/small mountains. However, the phone signal is on at maybe half the distance. My idea with what you guys said so far would be to use 2-3 devices passing through the info with long range, then hit an other device with a sim card using cell phone signal. might not be so efficient, and hills seem to be a problem with long range.
You can get a topographical map of your area and then plot out line of sight for your links,
as for LoRa distance, Andreas Spiess (the guy with the Swiss Accent) set a world record at 212 Km by using a balloon.
The Romaine project is for the construction of 4 hydro-electric power stations each of 1.5GW. Such a scheme must already have communications links using either landline or satellite. Even is cellphones don't presently reach the area extending mobile coverage to enhance worker safety (both in construction and operation) might be the way to go.
What is the windspeed monitoring for as it would seem to be an amateur project rather than someting official?
