Micro Hydroelectric power (plus solar if needed)

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PhantomNVD

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Topic # 150067 10-Jul-2014 12:08

So I've recently started investigating and costing the value of using the stream down at the bottom of my property to be the foundation for an (ideally) off-grid low-use household power supply. Since my search for good local information in this niche was turning up sparse and variable information I decided to start this thread (before derailing the excellent Solar one . and an excellent NZ company call EcoInnovation

To recap:

I have access to a stream which would generate 280w continuously 24hrs... To equate to a solar panel install, how much kWh/day is this... 24x280=6,720... Is this then a 6kWh equivalent?
How do I calculate batteries when output is so low, but 100% solid...

PhantomNVD: I already run a very energy efficient home. Wood burner (free wood) and gas califont and oven/hob ($50-70/month depending on wife's baking)

PowerShop tells me I use 5kW/day summer, and 14 in winter, so 6kW/day is all my use in summer and nearly half in winter.
My base load then IS nearly 300W, so I'd definitely need some panels to perk up the battery bank for night/winter use, though that's also when they're least/not productive :(

It looks to be $22000 to connect to 'the grid' after "development costs" so the battery bank
At 300W/h 24h/day I'd still cut my power bill in less than half annually, and pay off the micro hydro investment in a medium timeframe... even if I got $0 payback from the grid, so perhaps grid connected is simply a choice between battery bank vs grid use?

As I see it then (in my case) for such a small system, if I worked out how to run the base load directly from the hydro, the grid would just be factored against 'solar and battery' use at peak, vs grid fees, especially if grid connect >= solar install

AFAIK I'd need the battery bank to service a load greater than the <300w output, but as it runs 24/7 I should easily be able to replace this overnight and through the day when away and only running my base load?

Also, I only have 40m of the stream passing through my backyard and a 2m head, so dam would be

a)unlikely to be feasible, and
B) not really useful unless the head raised considerably to facilitate a higher power output?

Solar PV maths:

raytaylor:280 watts continuous is 6.7kwh of power a day
A 2kw solar system will provide 2.5kwh to 15kwh of power a day

PhantomNVD: Quick update... I just got an off-grid quote for my 10kW/day at 50,000 for Solar, and $55k if I used the mini hydro in the mix(!)

Apparently $35k for the base hydro install, and another $20k for solar to supplement for winter needs.

When the turbine is $2000, the piping $800, plus around $3000 for a good regulator, and $2000 to cable... Have to do it myself to make the numbers add up favourably I guess...

and another case example:

nutbugs: @PhantomNVD. A couple of comments about my experiences. (I probably should create a new thread about all this as someone suggested a while back - time is short and the todo list is long! It is on it though :))

We elected to install a second turbine and reduce the battery bank capacity so that we could cover a larger base load. We have plenty of flow rate in our stream so this wasn't an issue - simply installed a larger size pipe. We actually have capacity in the feed pipe to run three turbines. The excess generation is dumped into a hot water cylinder so we can have lots of outdoor hot baths :)

As per PM's - I will dig out our logic for battery bank sizing etc and get that to you.

The batteries are the weakest link overall when you consider the maintenance and cost. We are 6 or 7Km from the nearest grid point across unfriendly terrain so a grid tie is not an option. If it was - I think I would go that way. The downside obviously is that if the grid is down so is your alternative power! Not sure how they manage the Hydro connections - it will need a load somewhere I think?

We have 16 x 6v 225AHr batteries.
We are running 48v - so that is two banks of 8.

We really wanted to cover peaks above 1KW or so - of which there are not many - we keep everything very efficient - and a few hours outage. This has seemed to work well enough so far.

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Reply # 1086388 10-Jul-2014 12:38

It's all about the batteries...
https://gigaom.com/2014/07/09/at-a-big-solar-show-batteries-take-center-stage

PhantomNVD

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Reply # 1086391 10-Jul-2014 12:53

So here are some great priced batteries, although only current technology :)
http://www.golfcartparts.co.nz/index.php?route=product/category&path=73_95

k14

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Reply # 1086408 10-Jul-2014 13:37

PhantomNVD:Fair nuff, but wier is already there, consent is minimal for a rural property, as there is a 'farmers' allowance for water use already existent, so I guess I was just raging at the company inflation of the costing... Sorry? :)

I realise they in it to make something too, but for over 50% of the cost it seems a bit steep?

How much did the 5kW solar this thread started on cost I wonder?

Have you checked that with your regional council? I know the ORC allows a take for stock water but I'm pretty sure you aren't allowed to do anything else with that water apart from let your stock drink it. I'd say you would most likely need a resource consent for power generation. Most regional councils are fairly similar in most aspects of the regional plan but some things do change depending on which jurisdiction you are in.

wellygary

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Reply # 1086483 10-Jul-2014 15:34

If you are wanting to do the hydro thing properly you are going to need sign off from your local/regional council,

If you have 40 metres of the stream, then I would would look at building a small wier and a decent intake structure,
While you might not get much more head out of it, but it will increase your relaibility by a huge factor as you have a decent water store to get you through dry periods, as run of river hydro can be very fickle

trig42

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Reply # 1086485 10-Jul-2014 15:46

We (the wider family we) have a property that is off grid (there are no power lines running past it).
It is a large property (has about 10 houses and a lot of land) and has a stream running through the middle of it.

The stream would have at least 50m of fall through the property (probably a lot more actually), we currently take all our drinking/washing water from it.

I want to build a micro-hydro setup using a SmartDrive motor. We don't need a huge battery bank. The only things electric we have up there are lights, and most of them are LED - total draw for our bach would be about 50W peak at the moment. We run it off a car battery for a week (in summer, so not a huge usage of lights), and that battery will still start a car. Our idea is to get a couple of decent capacity batteries, and probably a hot water cylinder and rig it in such a way that once the batteries are at capacity, sink the energy into heating the water. That would save us Gas too. Looking at setup costs, since the pipes are already there bringing water to the house, it would be a very cost effective way of producing energy, plus it'd be fun to build.

There are a couple of videos on YouTube of people in NZ that have done this (one a guy in Nelson I think).

I'm not sure about sign off from Council - I'm sure if we told them, they'd want to know, but the water is coming out of the stream, through a pelton, and back into the stream.

PhantomNVD

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Reply # 1086527 10-Jul-2014 16:50

trig42: We (the wider family we) have a property that is off grid (there are no power lines running past it).
It is a large property (has about 10 houses and a lot of land) and has a stream running through the middle of it.

The stream would have at least 50m of fall through the property (probably a lot more actually), we currently take all our drinking/washing water from it.

I want to build a micro-hydro setup using a SmartDrive motor. We don't need a huge battery bank. The only things electric we have up there are lights, and most of them are LED - total draw for our bach would be about 50W peak at the moment. We run it off a car battery for a week (in summer, so not a huge usage of lights), and that battery will still start a car. Our idea is to get a couple of decent capacity batteries, and probably a hot water cylinder and rig it in such a way that once the batteries are at capacity, sink the energy into heating the water. That would save us Gas too. Looking at setup costs, since the pipes are already there bringing water to the house, it would be a very cost effective way of producing energy, plus it'd be fun to build.

There are a couple of videos on YouTube of people in NZ that have done this (one a guy in Nelson I think).

I'm not sure about sign off from Council - I'm sure if we told them, they'd want to know, but the water is coming out of the stream, through a pelton, and back into the stream.

sounds like you might even get by with one of these washing machine pelton generators (+/-600W at 45PSI) and seems an easy way to start off (if you have the pressure anyway)?

I think I need a custom-wound setup as i have a very low head/high flow scenario on my land...

PhantomNVD

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Reply # 1086528 10-Jul-2014 16:54

k14: Have you checked that with your regional council? I know the ORC allows a take for stock water but I'm pretty sure you aren't allowed to do anything else with that water apart from let your stock drink it. I'd say you would most likely need a resource consent for power generation. Most regional councils are fairly similar in most aspects of the regional plan but some things do change depending on which jurisdiction you are in.

not yet, though can't see where their issue might be as it comes out a culvert from a main road about half a meter higher than the stream, so there's no way fish etc. could ever go higher than my property anyway...
and as stated here

trig42:

I'm not sure about sign off from Council - I'm sure if we told them, they'd want to know, but the water is coming out of the stream, through a pelton, and back into the stream.

so I'd guess it's just $7k for a stamp on a form? anyone know what I'd have to show them to gain council acceptance anyway?

nutbugs

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Reply # 1087616 12-Jul-2014 09:10

In my experience councils will vary widely on their approach. Kapiti Coast council were really interested and accommodating. They seemed more interested in having a look at it all working than imposing consents etc. Horizons on the other hand were incredibly difficult to deal with and insisted on all sorts of reports and flow rate stats and attempted to impose some frankly unreasonable conditions. This was several years ago so things may have changed.

Bottom line is, as a default, I wouldn't consider consenting to be a trivial issue (assuming of course that you want it to be above board ;-))

nutbugs

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Reply # 1087617 12-Jul-2014 09:12

@PhantomNVD, thanks for kicking off this thread BTW :-)

nickb800

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Reply # 1087625 12-Jul-2014 09:59

nutbugs: In my experience councils will vary widely on their approach. Kapiti Coast council were really interested and accommodating. They seemed more interested in having a look at it all working than imposing consents etc. Horizons on the other hand were incredibly difficult to deal with and insisted on all sorts of reports and flow rate stats and attempted to impose some frankly unreasonable conditions. This was several years ago so things may have changed.

Bottom line is, as a default, I wouldn't consider consenting to be a trivial issue (assuming of course that you want it to be above board ;-))

Part of that will be the difference between a territorial authority (city or district council) and regional council. Regulation of surface water lies with the regional council, whereas a district council's statutory involvement would mostly be around the structure itself, which is more straightforward or possibly exempt. KCDC didn't have the power to impose many conditions on it. It would've helped that they are pretty keen on sustainability too.

Hammerer

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Reply # 1087632 12-Jul-2014 10:49

http://www.powerspout.com/assets/Published/public/PowerSpout-Model-Selection-Chart-Metric.pdf will give you some idea of what you might get out of your stream.

k14

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Reply # 1087637 12-Jul-2014 11:06

PhantomNVD: not yet, though can't see where their issue might be as it comes out a culvert from a main road about half a meter higher than the stream, so there's no way fish etc. could ever go higher than my property anyway...
and as stated here

You still need to ring up the council and ask. It is never as simple as that :) There are plenty of other things to consider aside from fish, disturbing the river bed, sediment, flood risk etc. You can just ring up the council and they should be able to advise you of the course of action you need to take to keep it above board.

nutbugs

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Reply # 1087669 12-Jul-2014 12:44

nickb800:
nutbugs: In my experience councils will vary widely on their approach. Kapiti Coast council were really interested and accommodating. They seemed more interested in having a look at it all working than imposing consents etc. Horizons on the other hand were incredibly difficult to deal with and insisted on all sorts of reports and flow rate stats and attempted to impose some frankly unreasonable conditions. This was several years ago so things may have changed.

Bottom line is, as a default, I wouldn't consider consenting to be a trivial issue (assuming of course that you want it to be above board ;-))

Part of that will be the difference between a territorial authority (city or district council) and regional council. Regulation of surface water lies with the regional council, whereas a district council's statutory involvement would mostly be around the structure itself, which is more straightforward or possibly exempt. KCDC didn't have the power to impose many conditions on it. It would've helped that they are pretty keen on sustainability too.

You are correct!I thought about that after I posted. Horewhenua was the local council, they had no idea and were not very helpful either. So maybe Wellington regional council also has a heap of hoops to jump through.

PhantomNVD

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Reply # 1087801 12-Jul-2014 16:46

Anyone had experience of doing this through Waikato council... You'd think that being very heavily invested in hydro in the main Waikato that they' debate knowledgeable and helpful (their site says they promote it) but what thought do you have on the consenting process?
A) do they weight the impact vs the outcome (I.e. My piddling 300w system maybe isn't worth any potential disruption to the stream)
B) since the stream coming into my property goes through a culvert 1/2 meter above the average pond height (mini waterfall, no fish ladder etc.) taking only 40m out of the overall stream from there to where it'll leave my property should do bugger-all to the environment shouldn't it?
C) cost of gaining consent vs getting 'caught' without it... If I just do it and ask later (if it turns out worth having) am I liable for a huge fine?
D) if I ring up to ask, do I lose plausible deniability? :)

Basically, for such a small outcome, would you bother asking before trying it out to see if it's WORTH having and paying (annual?) consent fees?

k14

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Reply # 1087829 12-Jul-2014 19:12

PhantomNVD: Anyone had experience of doing this through Waikato council... You'd think that being very heavily invested in hydro in the main Waikato that they' debate knowledgeable and helpful (their site says they promote it) but what thought do you have on the consenting process?
A) do they weight the impact vs the outcome (I.e. My piddling 300w system maybe isn't worth any potential disruption to the stream)
B) since the stream coming into my property goes through a culvert 1/2 meter above the average pond height (mini waterfall, no fish ladder etc.) taking only 40m out of the overall stream from there to where it'll leave my property should do bugger-all to the environment shouldn't it?
C) cost of gaining consent vs getting 'caught' without it... If I just do it and ask later (if it turns out worth having) am I liable for a huge fine?
D) if I ring up to ask, do I lose plausible deniability? :)

Basically, for such a small outcome, would you bother asking before trying it out to see if it's WORTH having and paying (annual?) consent fees?

B.) If you do anything with surface water that is not included in the regional plan then you need a resource consent. You need to talk to the council.
C.) Read the RMA, not only do the penalties include fines you could also be imprisoned. Most consents are given for a fairly long period, maximum is 35 years but most will be for circa 10-20 years.
D.) Ignorance is no excuse, you have no deniability to start with.

It sounds like you will most likely very easily get a consent but talk to the council. They aren't as bad as you think. There could well be a permitted activity rule that allows what you want to do. But without it you have nfi.

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