PICAXE Datalogger w/DIY Wind Turbine

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rWAVE

Member
As I PATIENTLY wait for the Linux-based PE, my usual daily Internet diversion recently led me to research alternate energy sources again.

No, I haven't bought into the WORLD-WIDE "global warming" HOAX, but rather have an interest and curiosity about other forms of energy. A year or so ago, I applied (sort of) solar to one of my hobby hydroponics systems with mixed results (unreliable DC pumps). I want to try again using very reliable AC pumps, which I am accustomed to using.

The plan is to used solar AND wind to charge batteries and have a PICAXE control the periodic "flood-and-drain" cycle in the hydro system. Thus, solar and wind charge the batteries, which is converted into AC by an inverter powering the AC pump, all under PICAXE control. Solar I get; Wind is new.

Over the past month, I have built a demonstration Wind Turbine, based on a laser-printer stepper motor. Without wanting to travel to merry old windy England or visit Hugh Piggott in Scoraig to functionally test my turbine, I decided on a "very scientific" garage-based test, utilizing a fan to turn my turbine's 24" blade. I was easily able to generate an open-circuit rectified 10 Vdc, enough to charge a couple of AA/AAA batteries.

Further research led me to charge/dump controllers and battery desulphation. I just HAVE to include these in my project! But another day.

At present, I want to collect some local wind statistics, hence the need for a datalogger. My goal is to use a small, self-contained unit that will date/time stamp voltage, current, temperature and blade rpm. Sampling rate needs to vary between 10sec and 5min over a period of up to 2 weeks and stored locally (unit will be in a remote area with no computer), until retrieved and downloaded into a computer for analysis.

First, I looked at Eagle Tree Systems eLogger v3; a great unit. Does everything I think I need (and for future projects as well) . . . except the live data stream must connect directly to a computer. I was hoping to intercept the data stream and store it locally in the remote PICAXE datalogger; that is until correspondence with Eagle Tree confirmed they use a prioprietary, compressed data stream, the format of which they will not share.

Second, I looked at PICAXE-18X Datalogger (AXE110P Documentation) and datalogging wizard in PE, which looks promising. By adding the optional RTC (AXE034) and EEPROM (AXE111), it appears it can handle a 10sec sample rate on all four channels for about 22 hours and a 5min sample rate for over a month. Output in CSV and I should be home free.

So, any differing suggestions on a datalogger choice?

Richard
 
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moxhamj

New Member
A brilliant project and one that I am going to do soon as well. Global warming or global cooling - it doesn't matter as energy is going up regardless and homebuilt power is going to get more competitive. The biggest hoax here are the somewhat over inflated figures for alternative energy. Wind turbines are quoted in peak watts when in a hurricane (eg 600W for a 1 metre diameter turbine), and solar is quoted at peak watts at midday. Real wind watts are more likely to be something like 30W per square meter, and real solar watts at midnight are, of course, zero. Building your own makes a lot of sense - for a start you cut out several middlemen in the retail industry, each of whom will have doubled the price since the product left the factory.

But what better way to prove what works and what doesn't than with a data logger? Then you can work out things like whether two wind turbines on short towers are more cost effective than one turbine on a taller tower.

The picaxe 18X datalogger is perfect. 10 minutes is a good sample period. And I suspect you will be so keen to get the data that you won't want to wait a month.

You will easily be able to get data into csv and if you have any problems, there are lots of people on this forum very eager to help.
 
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demonicpicaxeguy

Senior Member
i've recently ( last year ) seen a wind measurement project done by a science teacher which involved 3 load cells , a triangular piece of plywood , a broom handle and a big polystyrene ball

basically the broom handle was pushed through the ball with the other end in the middle of the triangular pice of plywood attached with a piece of 2x4" block of wood with a hold in it and a lot of wood glue, this weighed down with 3 house bricks sat on top of 3 load cells placed in a triangle on the ground,

he used an avr to simply readout all 3 values and send them via a serial cable to the pc with had a little vb program running on it that calculated windspeed and direction for several months,

doing it with a picaxe should be a breeze , (pun intended)
 
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manuka

Senior Member
DIY wind genes of course are prone to spectacular failure if even the smallest detail is neglected. Of course such woes usually occur during storms/middle of he night when you can't easily do running repairs- this is especially an issue in regions (such as here in coastal NZ) with significant wind.

I was at the "before & after" for a new commercial 5kW genes self destruction a few years ago (a substandard bolt sheared & unbalanced rotation developed), & strongly recommend you look at more durable alternatives!

All up solar PV are usually better value in the 10W-1kW range, if only because they can be near invisibly low profile roof mounted (& easily serviced), whereas wind genes' need costly towers to elevate them into laminar flow breezes. Mounting towers in the clear away from buildings will then need significant heavy duty cabling of course- allow US$20 a metre! This again is also a solar PV bonus- roof mounting gives shorter cable runs.

I've had a range of ~20W-100W PVs up here at my coastal NZ home for over 10 years (usually just charging deep cycle batteries in my shed), & no failures of any kind have resulted - although pronounced UV degradation of panels & surrounds has occured. In contrast, a modest DIY wind turbine I once had up (1970s) needed endless TLC, & the sight of it so annoyed neighbours that I had to take it down.

N.B. It's often pretty futile data logging wind just in your backyard anyway, as turbulent winds bounce off roof tops, trees & fences etc giving readings that are all over the place. You've got to get up WELL ABOVE ANY OBSTRUCTIONS - any wind resource handbook will tell more! Your remote site may be more tempting, but it's normal to log for at least a year to allow for seasonal variations. And don't forget remote wind turbines are visual magnets - any number get shot up by bored hunters after a target...

I'm a great wind energy fan however,& rustling up a few DIY Watts is a doodle, perhaps just for entertainment & education- use the Jaycar 1W gene shown as a guide. Simple logging of charging currents is easy with a 08M & bike computer => www.picaxe.orconhosting.net.nz/bikeamph.jpg .

EXTRA: The pix shows a 1kW wind gene & 80' (~25m) tower being raised.
 

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Dippy

Moderator
Very juicy Dr_Ac, though like Stan says they must have been expecting something to happen as I don't think they (yet) have a camera pointing at every wind turbine.

I found a site last year which showed dozens of turbine failures. I was on St.Helena (lucky girl) last Nov/Dec and one of their turbines had failed bringing the whole set to a halt.

I think they're only economical when the Government subsidise them.

Having got in my dig, I think a small set at home (assuming you are not my neighbour) sounds like a good idea.

I take Stan's point about siting and logging, but surely you want to meaure in exactly the place where you intend to site the turbine? Sometimes the ideal position is not the practical position. No point logging 50 feet up if you can only stick it 10 feet up is there? (Apart from the academic interest of height vs wind).
 
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MORA99

Senior Member
manuka said:
I believe that failure was due to braking malfunctions- & the filming indicated they expected something to happen!
Click to expand...
True, happened here in Denmark.
Unable to brake in a storm/brake too late..., apparently there are several brake systems, but the first system must slow the wings enough that the second system can engage.

If I remember right, the first is simply a change to the wings to make them less efficient.
 
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demonicpicaxeguy

Senior Member
MORA99 said:
True, happened here in Denmark.
Unable to brake in a storm/brake too late..., apparently there are several brake systems, but the first system must slow the wings enough that the second system can engage.

If I remember right, the first is simply a change to the wings to make them less efficient.
Click to expand...
they would always use a centrifugal braking system similar to the type of clutch you find in things like whipper snippers and chainsaws
 
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boriz

Senior Member
The trouble with any breaking system is how to dump the heat. Just look at that video again and imagine a disk break system. The disk would melt! Better to alter the pitch of the blades. Dynamic pitch control allows the turbine to rotate always at it’s most efficient speed. That’s why all the big turbines on a wind farm seem to go at about the same speed despite differing wind conditions.

The breaking system is probably just to hold it still during maintenance, like a hand/parking break on a car. It was probably the pitch control that failed in this video. Just my guess.

What impresses me is how fast it had to go before the blade failed. The tip speed may have been hundreds of mph. Those things are built to be as light as possible, but it still managed to destroy the cylindrical pylon (probably steel).

Excellent video. Thanks for posting it.

There seems to be a few different versions of the same video on YouTube. One of them is a slow-mo of the brake up. Very interesting.
 
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BCJKiwi

Senior Member
There is a recent commercial development of 'Household size' wind turbine here in New Zealand.

It comprises a single blade with a pair of short balancing arms opposite (Blade at 0deg, counterbalance arms at 135 and 225deg approx).

The trick is that the main blade is hinged and spring loaded so that when the wind pressure is too high it folds back toward horizontal thus reducing its effective diameter / resistance / power. Automatic, no feathering, braking, turning out of the wind etc.
 
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moxhamj

New Member
That sounds interesting - do you have a link by any chance?

It would need some maths. Wind would be pushing the blade back, but centrifugal forces would be trying to oppose that.
 
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BCJKiwi

Senior Member
Sorry but no, was just checking for some more info as I knew as soon as I had posted that more info would be needed!

It was shown on local TV the other day but have not yet found an on-line reference but will keep looking.
 
hippy

hippy

Technical Support
Staff member
Will household wind generators catch on ?

For me that's a simple question of "total infrastructure costs minus ( power generated times what that power would have cost from the grid )" over its lifetime.

While all in favour of alternative power I've just not seen that add up as cost effective. As energy costs rise it becomes more attractive but there is a lot of over-estimating what one will get going on.

It also seems to be a nonsense when we could have a single generator producing more electricity more reliably, more safely for many than each having a single generator. Unfortunately it seems many 'green campaigners' reject economy of scale and think everyone doing it for themselves is somehow philosophically better, even when that uses more resources and is less efficient.

Full marks to anyone who takes themselves off-grid and those who have no grid anyway, but for mainstream living I remain to be convinced of the benefits of wind generation, at least in most residential areas in the UK.

One factor never taken into account is utility company greed. If they lose money through people going more off-grid they'll increase prices to keep their profit margins high so what one gains in self-generation one loses in that which needs a grid supply. Unless one can go fully off-grid the gain may be hard to achieve.
 
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Dippy

Moderator
I 100% agree and always have thought so.

But, for some, a degree of independence is desirable and, of course clean energy provides a clean conscience.

And I support anyone developing clean energy... though the manufacturing methods/materials and delivery from China may add a few negative points. Anyway, we can only do the best we can do.

In the UK we have some people broadcasting the benefits of the wood-burner at home to replace gas/oil central heating. Well, imagine if all used them? Bunch of freaks.

Also the development and technology/skills learnt may have other benefits too.
I really must get on with my Solar powered steam engine which I've been thinking about for 15 years. Oh dear, 15 years of expelling CO2 and whatever happened to holes in ozone layer?

Ayway, rant over. Wimbledon is on. I'd switch on my solar/wind powered TV but it's cloudy and still.
 
hippy

hippy

Technical Support
Staff member
Yep, "how green is green", is something people are starting to ask, with more focus on the big picture than the smaller one and we're beginning to realise it's not as clear cut as it may first have seemed, most notably now being observed in the bio-fuels versus starving the planet debates.

The biggest obstacle, as I see it in the UK anyway, is that those who can save the planet don't have the resources to save the resources, which usually means having to spend to save money. We're stuck in a self-created chasm and are desperately trying to dig ourselves out using half-measures ( or less ) which make us feel good but don't fix the big problems.
 
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Dippy

Moderator
Tricky innit. And a lot of people are of the same mind.

Say, instead of 'suffering' , why not do something to get on the bandwagon?
 
hippy

hippy

Technical Support
Staff member
I've come to the conclusion that the world is buggered and doomed, self-interest, greed and apathy will see to that, and while I despair at that I'm fast approaching a position that I couldn't really care either, que sara sara. I've got my "told you so T-shirt" and am readying my old age to be sitting on the side-lines watching the world burn - assuming I'm not euthanased to save resources for others.

I've done, and will do, as much as I can but if people won't wake up to what needs doing and do it I'll be dragged down with them regardless of whatever I do.
 
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Dippy

Moderator
Cheer up me old hipster.
Don't turn into Marvin, old chap.

Even I can remember hearing in the 80s that the oil would be finished in 20 years - it was an absolute cert broadcast by the doom-mongers of the time.
And, apparently, by now, we'd all be working from home with the computer revolution.

But on your own, or even with the full Pub-Quiz team, you can't do anything sadly.
The world and it's strange population will be here in a hundred years, don't worry (I know - you're not worried).

There is (was?) a shipload of Chinese arms destined for Zimbabwe kicking around down South Africa way, you could start the ball rolling by sinking it. A nice PICAXE controlled long-range Spearfish. Go on, you can do it. You can launch it from DPG's trans-oceanic canoe. But don't let Stan build the guidance electronics, as all the components will fall out of the breadboard when it hits a bump :)
 
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demonicpicaxeguy

Senior Member
Dippy said:
Even I can remember hearing in the 80s that the oil would be finished in 20 years - it was an absolute cert broadcast by the doom-mongers of the time.
Click to expand...
ah the good ole days where people would believe the sky was falling if it was said on tv, oil is an interesting subject and so is some of the hypocrasy and blatent lies behind it's supply and refinement not to mention the taxes that keep us dependant on it and the alternatives not financially feasable,

oil is somthing that is probably not going to run out before humans are extinct the alternatives for fuels use is interesting because under the surface of all the government support for them , various governments are doing their best to keep alternative fuels as a reality out of the realm of feasability with taxes in convient places,

i like how down here in Australia they keep saying "oil has surged to this" in the news, it's amusing that they go very quiet when the oil price takes out character plunges by $10 to $15 even $20 in one day

total or near total energy independance for average person will never become a reality while governments around the world keep pandering to the energy giants, it will always be the realm of the educated and "willing to get off your butt" few just like the various people on these forums

Hippy , where did you get the "i told you so t shirts" - i want one too,

for those of us who want an interesting read
http://en.rian.ru/world/20071208/91488137.html - irans stops selling oil in US dollars

http://www.atimes.com/atimes/Middle_East/JE28Ak01.html - surgical strikes in Iran,.....
http://www.presstv.ir/detail.aspx?id=53925&sectionid=351020101 - while we're here lets have a war
 
lbenson

lbenson

Senior Member
A lot of puff in those articles referenced by DPG about the provocation of the U.S. sending a second carrier into the Persian Gulf in early May--not much about the return of the carrier it was relieving to Norfolk on June 4. Just a token of the slant taken by PressTV.

It's interesting to ponder how it is taxes which are keeping us dependent on oil--that does have me perplexed.

A recent Scientific American article projected that solar power, with hydrogen production to fill in the sunless gaps, could supply most U.S. energy needs by 2050, with government subsidies of less than the cost of the Iraq war (not the way they put it), and using many thousands of square miles of desert in the southwestern U.S. Australia could use similar desert areas, but I'm not sure where that would leave Great Britain.
 
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rWAVE

Member
Shame On All You Thread Thieves . . .

Since one of my few posts appears to have been hijacked and my datalogger / turbine have blown away in the wind, I'll bite :).

Per Ibenson's reference, I also believe solar is currently our best short / long term solution and we in SoCal are doing something about it.

Our two largest utilities, Southern California Edison and San Diego Gas & Electric have signed the world's two largest solar contracts with Stirling Energy Systems to generate 1,750 MW of power, and in the process of development with Sandia National Laboratories have broken a nearly 25-year old net efficiency record of 29.4% with an impressive 31.25%.

And I read somewhere (can't find the source right now :() that if we went out to our desert and put these Stirling engines in an square area of 100 miles on a side, it would supply ALL the energy needs of the United States!

At the consumer level, a major, nationwide solar implementation in a short period of time can be achieved when cost and manufacturing capacity reach a tipping point . . . Nanosolar might be one such company to do it.

Richard
 
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manuka

Senior Member
Impressive! In spite of -duh- only working in daylight,you really can't beat PVs. On top of long life,no moving parts, low profile, easy integration etc they're of course scalable & readily maintained. With prices ~US$5 a Watt they already are THE winner for many off grid setups. The problem is often now energy storage...

IMHO wind really only tempts when there are very poor sun resources, or for large scale (MW range) projects.
 
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Mycroft2152

Senior Member
Let's not start a flame war about solar versus wind power. The bottom line for mass acceptance will be the one with the lower cost and higher profits. ***

Intel has just announced its entry in to the solar market.

There will always be special cases where cost is not a priority.

Myc

*** and yes nuclear power will make a comeback for the same reason.
 
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moxhamj

New Member
Re "Shame On All You Thread Thieves . . ."

Yes, ok, guilty as charged.

manuka, energy storage is a problem, but I read an interesting solution somewhere recently. Instead of using old oil wells and filling them up with CO2 from coal power stations (which is a bit dodgy coz you need to burn more coal to purify the CO2), the proposal is to use compressed air to store solar/wind energy. Pump it down into the hole, then run it back out again when you need the energy back.

rwave, yes we did hijack your thread. Sorry. What was the original question, and did we actually answer it?
 
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rWAVE

Member
All's Well . . . Questions Answered!

Sorry Dr. Acula, it was my pitiful attempt at humor (humour?) . . . back to the cave for me!

Richard
 
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Dippy

Moderator
Sorry, your thread got a bit digressed. I can only assume everyone agreed with Dr_ac (post #2 or #3) that the PICAXE Data Logger was fine. Job done.

There are a zillion Data Loggers on the market but as this is a PICAXE thread I think you'll have to accpet the enthusiasm for a PICAXE based project. Yes/No?

I thought the rest of your post was to describe what you wanted to do. Were you expecting opinions or design suggestions? You didn't hint....

Anyway, you'll have plenty of time to get designing/building while you wait for a Linux product :)
Personally I'd get myself a cheap little Windows machine and get on with it.

Oh btw, it sounds like a really interesting project.
 
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