Is hydro a practical possibility here?

[John Heath]

I have a email friend Manfred who I share a fondness for antique radios with. One day Manfred decided to build his own paradise in the mountains of South America. Being a clever fellow he made sure there was water higher than the house he planned to build. The end result was a self made hydro system , 5 K watt if memory serves , to heat and cook in the house. I know you are going to like this from what I am reading which is why I am making this post. He is an excellent photographer so the complete construction from beginning to end is well documented.  Try to imagine you are doing this not him to live a life that could have been. Enjoy.

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

I liked the photos.

But as he has built it I don't think it has a chance of working for long.

How is the frequency controlled ? The generator is designed to run at around 1500 rpm to output 220v @50hz.

The home made transformers are they variable frequency?
Maybe he has some one controlling the water flow.

sorry nice photo shoot .
bill

Hi Bill

I wrote Mr Manfred and told him of the interest in his home made hydro plant along with a link to this thread. It is my hope he will join in and give precise answers to your questions.

I can tell you what I know.

The hydro station is not a car alternator with a fan on it. It is a top down design housed in solid concrete. Frequency control is not easy if there is not a grand grid to sync lock with. If memory serves a sudden drop in power demand leads to a fast triac power dump to a dummy load followed by a slower trimming of the water valve. Knowing Manfred the critical damping of this feed back system is probably as close as possible. As to a hand wound  transformer. I will venture a guess that the educational system in Chili puts an emphasis on the  fundamentals of electrical engineering. Theory is one thing but can you build it with your own hands?  Iceland and Japan is the same where engineers walk around with tools in their hands not laptops.   

[bills]

Please don't miss understand me I think that the project is great!
i am concerned as to how the water flow is controlled?
NO I DON'T think it is BS Sorry if I gave that impression .
My question was how do you control the flow? I must be missing something.

regards
bill
 

[IanB]

Please don't miss understand me I think that the project is great!
i am concerned as to how the water flow is controlled?
NO I DON'T think it is BS Sorry if I gave that impression .
My question was how do you control the flow? I must be missing something.

Frequency control is described in some detail in the web pages you linked to.

Gross control of power input is regulated by hand, by admitting flow to one or more water jets feeding the reaction turbine. This sets the available power and maximum power output according to expected demand.

Frequency is regulated by adjusting the load on the generator electronically. If the frequency is too high the load on the generator is increased (by dumping power), thereby slowing it down. If the frequency is too low the load is reduced. Clearly the base load must be lower than the maximum available power for this to work so there is headroom for the regulation.

Regulation can be controlled cycle by cycle at the zero crossing point, or it can be controlled at high frequency within each cycle. The former approach gives a cleaner waveform but slower regulation with occasional frequency dips. The latter approach tends to produce a noisy and irregular waveform that needs filtering. It is also possible to regulate frequency by automatic control of the water flow, but this is even slower to react and is rarely used.

At the system in question it seems the constructor settled on per cycle regulation since small transient frequency variations are not important for the loads connected to it.

[onlooker]

The Powerspout's power calculator looks to be specific to their products. Comparing to the theoretical power, their products have an efficiency about 40%. The modern hydropower is about %90 efficient in hydro-to-electricity conversion (wiki). 

[mtdoc]

The Powerspout's power calculator looks to be specific to their products. Comparing to the theoretical power, their products have an efficiency about 40%.

Their calculator takes into account pipe losses and gives a similar number to several other calculators I've compared it to.  Also, you need to be sure to set the proper type and number of turbines for the head and flow.

Their turbines are well regarded.

The modern hydropower is about %90 efficient in hydro-to-electricity conversion (wiki).

Reference?  Perhaps that is referring to turbine efficiency only?

No micro hydro system is 90% efficient when all losses are accounted for - not even close - more like 50%.

[onlooker]

...
Their calculator takes into account pipe losses and gives a similar number to several other calculators I've compared it to.  Also, you need to be sure to set the proper type and number of turbines for the head and flow.

I was trying to explain the difference between you and IanB (and others). The 40% I estimated was the turbine conversion efficiency assuming zero pipe loss (using their calculator).

Their turbines are well regarded.

I did not dispute this in either way.

Reference?  Perhaps that is referring to turbine efficiency only?
 

 

I mentioned wikipedia.

No micro hydro system is 90% efficient when all losses are accounted for - not even close - more like 50%.

I do not know  enough to say something specific about a system at kW level. My feeling is that hydro systems are very scalable. I could be wong.

Edit: according to wikipedia under "micro hydro", the typical efficiency of various systems is about 80 to 85 % with Kaplan being around 90%.

[mtdoc]

Part of the problem is that the term Micro Hydro is commonly used to describe a broad range of power system sizes. Anywhere from systems generating 100 W from small streams, to systems generating 100 KW from rivers.

The Wikepedia Micro Hydro page calls anything below 5kW "pico hydro" but I can tell you from personal experience researching and following this topic over many years that no one uses that term for the small, usually 100 W to 1kW systems that individuals use for single homes. Micro hydro is the term commonly used - even for very small systems.

The Wikipedia article states:

Power from such a system can be calculated by the equation P=Q*H/k, where Q is the flow rate in gallons per minute, H is the head loss, and k is a constant of 5,310 gal*ft/min*kW.[7] For instance, for a system with a flow of 500 gallons per minute and a head loss of 60 feet, the theoretical maximum power output is 5.65 kW. The system is prevented from 100% efficiency (from obtaining all 5.65 kW) due to the real world, such as: turbine efficiency, friction in pipe, and conversion from potential to kinetic energy. Turbine efficiency is generally between 50-80%, and pipe friction is accounted for using the Hazen–Williams equation.[8]

It then goes on to discuss 6 specific turbine types - none of which are the - commonly used for small systems - pelton and turgo turbines. Those are what the leading small turbine manufacturers,  PowerSpout, Harris Hydro, and Energy Systems and Designs manufacture and sell.

Regardless of the turbine type, I think you'll find that the various calculators for all turbines you find online will give you very similar results once you control for the inputs and the factors used to do the calculations.

[onlooker]

Yes, I have noticed the typical conversion efficiency for microhydro systems varies from about 50% to 90% by different info sources. The below is a quote from DOE resources (http://energy.gov/energysaver/microhydropower-systems)

"Microhydropower systems usually generate up to 100 kilowatts of electricity.
...
Pelton wheel -- uses the concept of jet force to create energy. Water is funneled into a pressurized pipeline with a narrow nozzle at one end. The water sprays out of the nozzle in a jet, striking the double-cupped buckets attached to the wheel. The impact of the jet spray on the curved buckets creates a force that rotates the wheel at high efficiency rates of 70–90%. Pelton wheel turbines are available in various sizes and operate best under low-flow and high-head conditions."

Presumably, 70% is for systems under difficult design parameters (e.g. small, low budget, non-optimal water conditions,...).

In fact, all such discussions are secondary to my original main point: that is to explain why the number that PowerSpout's calculator gives is much lower than the theoretic value by the power fomula. It is due to that the calculator already figured in the about 40% efficiency of their products.

As to whether 40% is too low or to high, apparently there are many different angles to look at it as we have already seen.

[G7PSK]

For low heads an Archimedes screw turbine is probably better, a piece of old grain auger might make one.

 https://www.renewablesfirst.co.uk/hydropower/


I think the owner of the Homo Ludens site used to be on this forum. But I cannot remember the name he used here.

[_Andrew_]

Having fun trying to convince the Environment Agency that they should allow us to take over the operation of the wears that are in place of an old lock gate and Mill. But there being very resistant to the idea in favor of putting in a fish walk.
It is also proving difficult to to get the annual flow rate data out of them. For a Archimedes screw turbine 250 liters per second is probably about the lowest flow rate practicable for a 1m turbine.
Guess it is coming to playing poo sticks to try and determine the flow rate and measure the aria to work out the volume. Fortunately there is a channel down stream of the site thats safe to wade into when it is not in flood. Should be able to gain a good estimate.
The site lends its self for a Archimedes turbine as two of the four weer gates were installed in place of the up stream lock gates leaving the concrete walled lock channel open and plenty of room for the 22 degree angle needed for the Archimedes turbine channel to be installed, and there is also a good 4m drop. Extraction rights not an issue.

It is very appealing the idea of producing energy more or less 24/7 in comparison to solar.
In theory an Archimedes screw turbine will be better for the over all health of the river as fish ect can pass through the turbine ether way with little or no harm. Tests have already shown that Archimedes screw turbines cause less harm to fish that fish walks.
They are also less susceptible to water borne debris clogging them up so less screening is required in comparison to pelton wheel water turbines that can require screens for objects down to 2mm in size. 
They also can have a very long life span.

[mrpackethead]

Ueed a permit to use natural hydroelectric power.

And maybe you even need a permit to use metric units.

[mtdoc]

The best low head turbine for small - single home sized projects I've seen is the Powerspout LH

Here's a nice video of a largish installation using 2 of these in Romania I saw posted on the Midnite solar forum:

Powerspout

[G7PSK]

Another solution would be this floating wheel design, easy to make and very robust.

https://youtu.be/p4scG3cuL7I

A good site for renewable energy is. http://www.fieldlines.com/ 

[Mechanical Menace]

Seeing as there seems to be a few distributors for them over here I'm looking into Powerspout's offerings around the 200wh mark but while I'm doing that I'm going to get some practice in with a welder and repurpose an alternator just to play around with and get more of an idea of the actual practicalities of getting something like this up and running.

I'm also going to have to look into some sort of storage mainly to fulfil my peak power requirements. But, even though something like this should produce more than enough power to run my home, I would like to have a couple of days backup just in case. I can't see me needing it with micro-hydro and a small solar setup but I'd rather have too much and never need it than not enough and be having to upgrade. Such a shame I have zero chance of being able to put up a small wind turbine as well.

Thanks for all the suggestions, links, and just general nattering about the subject. It is much appreciated.

[tszaboo]

Dont forget, that you have probably now a constant heat source, that can be used to heat or cool the house if you slap a heat pump on it.
I would ignore the storage systems. If you have net energy metering, it just doesnt matter.

[mtdoc]

I would ignore the storage systems. If you have net energy metering, it just doesnt matter.

It depends. If he is off grid or has frequent extended grid outages he will need to be able to meet peak loads. Unless one has a very large hydro system - it is unlikely that it will be able to supply peak loads without battery storage and inverter.

[Mechanical Menace]

Dont forget, that you have probably now a constant heat source, that can be used to heat or cool the house if you slap a heat pump on it.

Given that I'm in the UK I have no real need for cooling and very rarely use my heating. Last year it was on maybe 4 days in total and that was only for the benefit of guests. Good thought for others but not worth it for me.

I would ignore the storage systems. If you have net energy metering, it just doesnt matter.

It depends. If he is off grid or has frequent extended grid outages he will need to be able to meet peak loads. Unless one has a very large hydro system - it is unlikely that it will be able to supply peak loads without battery storage and inverter.

I have no real need to go off grid but want to. I also at worse use 6kWh in a day and on average 3*, with peaks under 3.5kW. With such low usage a hydro system large enough to provide my peak power would be total overkill.

*And hopefully I can get that down.

[tszaboo]

Given that I'm in the UK I have no real need for cooling and very rarely use my heating. Last year it was on maybe 4 days in total and that was only for the benefit of guests. Good thought for others but not worth it for me.

I always forget that the average thermostat setting in the UK is a freezing 18 degrees.

[mtdoc]

I also at worse use 6kWh in a day and on average 3*, with peaks under 3.5kW. With such low usage a hydro system large enough to provide my peak power would be total overkill.

*And hopefully I can get that down.

Well done!.

BTW, I've been meaning to ask: Ishmael, is that you?

[Mechanical Menace]

Well done!.

Well thanks but that wasn't bragging, just context. But I will admit the fact I don't do without my gadgets or conveniences is a bragging point lol.

BTW, I've been meaning to ask: Ishmael, is that you?

Ok I know that's going to be a reference to something, it's even firing up that "I know that but don't know why" part of my mind, but I'm having a thick moment and can't pull it together 

[mtdoc]

BTW, I've been meaning to ask: Ishmael, is that you?

Ok I know that's going to be a reference to something, it's even firing up that "I know that but don't know why" part of my mind, but I'm having a thick moment and can't pull it together 

Highly recomended!

[leo_r]

My dad recently built a micro hydro scheme on his land in Scotland. Peak power is 8.6 kW, but average is more like 4 - 5 depending on season. Head is maybe 20m or so, coming from 2 intakes (2 streams merge into one on the property).

He used a turgo wheel from these guys coupled to an induction motor (rated to 10.8kW) running in reverse through some control electronics supplied (I believe - this is from memory) by sustainable control (not that there's much on that site). I think the person who runs that company also wrote this book, which I imagine covers the electronics in some detail.

He's got 4 quarter turn valves being electronically controlled to control the flow rate. Essentially the generator is brought up to speed with no load, and then when it reaches 50 Hz its connected to the mains. The control system then adjusts the valves based on the water level at the intake to the pipes (measured using current loop pressure sensors). As his setup uses 2 intakes and 4 quarter turn valves (rather than the 2 that the original control system is designed to work with) we had to implement a custom control system using a Crouzet CPLD. It reads the 2 intake depth sensors and controls the 4 valves, providing spoofed depth information to the control system to keep it happy.

I think the total cost of installation was about £30k. I'm not sure exactly where that went - work included building 2 intakes using pre-cast concrete planks, obtaining and getting delivered the plastic pipes, burying them, building a wooden hut for everything, buying the control system/generator and getting the necessary permits. He hired an environmental consultant to sort out the permits and a builder did most of the larger installation work. I think he did most of the rest himself.

In the UK the government pays a tariff of around 21p/kWh for all electricity generated by hydro schemes, on top of the 5.4p/kWh that they'll buy it from you for. That means the scheme will hopefully break even in 3 - 4 years.