PV Tracking

[offthegridandy]

Hi,

Does anyone have accurate figures on increased output achieved by tracking the sun. If the gains are sufficient to justify I thought I might "mobilise " my array.

We have 1.6Kw of pv which performs v well. Panels are aligned east west and set at 37 degrees or so with no shading.  Panels are on the ground not the roof. Before investing in another array I want to be sure I'm getting the maximum putput from existing kit.

I found in the back of my store a 12 V hydraulic pump recently . Forgotten I had the thing (trouble with KRAFT disease!). Hydraulic pump can lift 2 tons and me thought "this could drive a turn table with the PV panels on. Track der sun and make more leccy. Thought I could use a timer to simply turn on and off at half hourly iuntervals to rotate a set increment.  Haven't even got the fag packet out yet but would like to hear thoughts on.




I'll have to reposition array if I go ahead but space is not an issue.

Cheers

Andy

[biff]

hi andy,
        ecogeorge installed a very nice tracker system a few months ago ,so he should be able to come up with figures.this time of year,when the sun is low in the sky,would not make a lot of difference,percentagewise but from march onwards the improvment figure is around 20percent which makes it worth it as long as you can make your own reliable tracker because the lorenze version is horribly expensive.
       if you are going to make your own,you need to be aware that the panels have to be anchored to withstand storms,etc,so thats where the engineering comes in,like i said before in a previous post i intend to use a hiab slweing gear driven of a 24 volt hydraulic pump controlled from the house. in midsummer we should be able to reduce the power on demand by turning the array away slightly..its an idea, !!
                                                                                    biff

[martin]

there's several threads on the subject - here's one of them - http://www.navitron.org.uk/forum/index.php/topic,6115.0.html - I'll commend the "Redrok" link if you want to DIY on a budget

[offthegridandy]

Thanks Biff, Martin.

Gee that guy over at Redrok is a busy boy isn't he.  Just doing all the posting never mind creating stuff.

Following the links you supplied it looks like I've got potential for overall gain of +/- 25%.  As this is DIY, cost would be low, certainly less than cost of one more panel.

 I have motive power and rear axle from transit to provide "hub"  rest of cost is metal framing and concrete base.  I'm thinking of keeping array at ground level, perhaps an old jockey wheel at each end to provide extra support. I agree that I must consider wind issues, I'm sure were not as exposed as you Biff but it's still a real issue here. I sure has heck don't want my babies flying up the field, might hurt the cows, ah. Now they produce loads of sausage should I go for the worlds first methane powered solar tracker.

[Nicedad]

I have no doubt that the Redrok tracker is the best built and technically advanced unit. The trouble is obtaining one. You have to Wait several months for delivery (this is not just my experience) I am still waiting on replacement sensors ordered late October. After sales support is also poor. I think he's underpriced and certainly doesn't charge for delivery. I have lost patience and brought a complete new unit from Austrialia. This works well and was promptly delivered and has good after sales support.

[ecogeorge]

Oh    can you post details of the australian one ? I've been looking at aus' units also.

rgds George.

[skyewright]

Following the links you supplied it looks like I've got potential for overall gain of +/- 25%.  As this is DIY, cost would be low, certainly less than cost of one more panel.

Another way to work out the potential would be to plug some figures into the on-line calculator at PVGIS:
http://re.jrc.ec.europa.eu/pvgis/apps4/pvest.php
As "Radiation Database" choose "Climate-SAF PVGIS"
For the rest just provide the relevant figures, and tracking options.

If you tick the "show horizon" option and their idea of your horizon is off the mark it's not hard to provide a custom horizon file of your own (it's just a list of horizon angle around the compass, starting from East . For more detail, click the [help] link just right of the Calculate button).

[lee ronin]

i cant give you figures but my lorentz  tracker has 700w on it at the moment and it's leaving standing the 1650w on the roof ,i do get some shading on the roof ( 1pm and 3pm but the tracker is awake doing its thing
way before the sun gets round , and the same at night

imoa they are worth every penny

[offthegridandy]

G Morning,

Thanks lee and skyewright.

Checked the figures again on PVGIS, the calculations show a good 25% boost, so I will be getting a piece of charcoal sharpened, so I can scratch some rough drawings on the old cave wall. I'll come back with more details as time and weather allows.

Cheers.

A

[offthegridandy]

found these 2 links which are interesting

http://www.builditsolar.com/Projects/PV/Archimedes-MSA.pdf

http://zomeworks.com/files/pv-trackers/copy_of_Homepower_june2004.pdf

Andy

[ecogeorge]

I see there is a tracker set up appeared in a back garden just off the A48 near Stroat (Glos -Chepstow road), -looks like a Lerentz - anyone any info ?  or will I have to introduce myself to have a look?

[Nicedad]

Hi ecogeorge

Sorry for the delay in replying, just got back into the UK last night. The Australian unit I brought came from ebay. Just type in solar tracker on the search engine. The unit I have is the boxed unit without cables. You need to let him know that its for the Northern Hemisphere and he will set it up according. Although its rated as waterproof I have enclosed it in a clear plastic bag and there is no detriment to performance.

The unit I have is the 12v. The linear actuator is 36v but runs OK with the 12v applied but as expected is slower. There is a downsid, at the end of the day, the unit returns to the start position, but only as long as it can do it in 10 mins. Sometimes it won't get fully back to its start position. It will first thing in the morning though. The redrok unit doesn't have this time limitation.

That said the Australian unit is not so twitchy.       

An update on the redrok sensors I ordered. They were received by my darling wife earlier this week. The order was placed on 19th August 2011.

[lee ronin]

geroge how did your tracker do in those bad winds ? mine showed signs of some flexing but stood up to the wind bashing