Hydro with grid tied inverter and power outage

Welcome to the forum Poxito,

I guess you are in France, so you will need to see what is available in your region of the world and meets your local Grid Tied system laws.

With Hydro (and most wind turbine), they have an issue with how they work. They need constant load or destination for their energy (such as a battery bank, Utility Grid, or "dump load" resistor bank) to keep them running at the correct RPM. 

If you have a loaded turbine (water or wind) and cut the load (such as a utility failure), the turbine needs to have its water flow turned off/down, or an alternative load needs to be supplied to keep the turbine from overspeeding (wind turbines can actually self destruct, throw blades, knock towers down, etc. and will usually have multiple extra safety features such as a mechanical brake, short the turbine, turn away from the wind, feather the blades, etc.).

The SMA system (that I am aware of--I am not an expert here)--Basically uses the power from the solar array and its internal AC inverter to generate power to a second circuit (in the USA, 120 VAC @ something like 10-15 amps) that manually needs to be turned on for backup power (during the day) (a large 3,000 Watt+ array to supply enough power for a single AC load circuit during daylight hours).

This system is "relatively" easy to do (from an engineering point of view) because solar panels can supply loads or not--And they will not damage themselves if the loads are removed (there is one class of solar panel that can damage itself--But that is not an issue for 99.99% of the population).

What you really need is a Wind Turbine style of electronics package. One that accepts the variable output of a water turbine, and has the controls to shutdown the turbine in the event of a load failure. To do that, and supply stable AC power without a battery bank is difficult--Turbines can take seconds to respond, and your refrigerator turning on may take >600 Watts starting, and after a second fall back to 120 Watts running.

The typical method to "solve" this problem is to add cost... A large battery bank to buffer your loads, and a Hybrid AC inverter, with charge controllers (charge controller for the turbine, charge controller for solar, backup genset controller, etc.).

Hybrid AC inverters are very common these days (and many Off Grid inverters include  "GT mode" for almost free)... The can generate AC power from the battery bank (like and off grid AC inverter), and they can also, when the battery is full and you have Utility Power, feed the excess power from your charging sources (turbine, solar, etc.) back to the AC grid (using the grid as "dump load" to avoid overcharging the battery bank).

All of that is relatively well known and the hardwave and experience is out there. Not cheap, and the battery bank certainly adds costs and maintenance issues (cheap batteries may last 3-5 years, better batteries may last 8 years, or even 15+ years).

This is not a trivial system design. And hydro is a bit of twist. Most people do not live in a location blessed with lots of water flow and elevation drop to run hydro power. So finding hardware that can do what you need for hydro may also need some work on your part (or an engineer) to do the control system interface for your turbine/water flow.

You will have to look at the reliability of your utilty power (down for 1 week a year, highly unreliable, or what). And what it is worth to you. Generally a hybrid off grid system--The power is "not cheap" when you roll in the costs of all the equipment, battery bank, and replacement battery bank every X years (the electronics generally need replacing every 10+ years too when/if they fail).

This company seems to offer a fair amount of Hydro Power support:

https://www.backwoodssolar.com/products/microhydro-power
https://www.offgridbootcamp.com/off-grid-hydro-power-101/ (more hydro links)

You might also try contacting member "clockmanfran" (@clockmanfran)

Leslie has posted about his AC inverter projects and book here... He is in Normandy, France and may be able to better help you with your project, or at least give you some ideas/links that would support your hydro project:

https://forum.solar-electric.com/discussion/354711/2nd-edition-6kw-ozinverter-build-book-manual-pcbs

You can message him here through our forum software:

https://forum.solar-electric.com/messages/add/clockmanfran

Good luck and let us know about your progress.

-Bill

Poxito,

As a moderator here, I can "see" your IP address... I use an IP locator website (usually this one):

https://www.iplocation.net/

Works well for general IP addresses... But for mobile phone/satellite not good... And obviously Proxy servers and server farms hide the end address (or are reused over wide regions).

Here is a guy that documented his (successful--I think) hydroelectric adventures:

http://ludens.cl/paradise/turbine/turbine.html

Good luck and have fun!

-Bill