Renewable Energy Log

April 2007
27th - 12v Items

March 2007
24th - New Monitor Box

January 2007
30th - 90Ah SLA Battery
26th - New Charge Controller
10th - 18w Panel Smash

December 2006
23rd - RE Radio Shack
4th - RE Laptop
2nd - 10mm LED Torch

November 2006
21st - Panel Stand

October 2006
16th - More Portable Ideas
10th - More Portable Ideas
8th - Portable Ideas
2nd - 60w Array

September 2006
20th - 18W eBay Panel
20th - Solar Monitor Box
17th - CCFL Lights
17th - 17Ah Battery Datasheet
5th - SLA Batteries

August 2006
6th - 6W Folding Panel

Copyright © 2006-2007
Andrew Whyman

Log of renewable energy activity:

Ive decided to keep a log of all the renewable energy things that I do and report information about my array etc. Its not only something I can read back through but its also something that viewers of this site can look through to see what Ive been doing to the system and how well its coping with what Im doing to it etc.

Tuesday 31st July 2007:
Sorry about the lack of updates recently. I've been busy camping and trying to find a job.

I've been running my laptop from my system for a few hours on an evening the last few days as I've been hitting full every day. I'm using my laptop now but on the mains as the RE battery is still charging but with only 1A of charge. I really need to get some more panels, preferably 60w if I can to boost the incoming power some more and hopefully allow me to run my laptop purely from solar rather than charging the battery and running off that.

Saturday 23rd June 2007:
I've put the 90Ah SLA on a mains charge for this first time ever today. Its lasted 6 months without a mains charge but the recent rain has taken its toll and ive really drawn it down. 12.2v under a light inverter load of around 5 amps. It was down to 12.6v under a 2.4A load so I thought it was best to put the mains charger on. The mains charger consists of a 13.8v regulated CB power supply. Its directly hooked to the battery through a fuse. Its only a 3A/5A charger but it will at least get it back up to a good charge. If I don't do it I fear it will sulphate.

I'm going away next week for a week or so too. It will give the system chance to charge and put in a nice float charge. I think I'll leave it on 14.5v because it almost certainly wont be charged by the mains charger very quickly. Assuming 50% DOD it will take 15+ hours to charge to full and I'm not leaving it on overnight. The hum from the transformer is too loud to sleep with it on.

Saturday 16th June 2007:
Its been a dull week most of the week resulting in very little solar insolation. However Im still managing to get into the high 13's and sometimes hitting 14v with under 300mA current coming from the panels. Ive hooked up my 21 10mm LED light over my bed so I can use it for reading. It only takes 180mA compared to the 420mA of the CCFL. Its more than ideal for reading and the solar shed light doesn't come into much use anymore. I might relocate it for doing another job.

My car battery is charged and it sitting at 12.90v. Im not sure if this is normal for a car battery or not as this is the first time Ive worked with charging one. I assume its normal because their voltages are slightly lower than SLA's.

Friday 8th June 2007:
Its been a busy old time recently. Ive been up to lots. Ive been away camping with a basic solar system. I used a 1.5w solar charger and my 7Ah SLA which I used to power some chargers for phones, gps, AA/AAA batteries and torches. Despite being small it lasted the 3 day trip with little drain.

Ive just put the 1.5w charger on the other 90Ah SLA (the repaired one) to keep it topped up. I forgot to put it on charge after I used it to try and jump start a car (which failed because the starting battery had a shorted cell and wouldn't take the charge, it just wasted it). Its been on a little over 24 hours and Im going to check it tomorrow to see how much it has charged. Im hoping it wont need a charge controller on it with it being such a small panel.

My car battery died on me the other day. Its been slowly getting worse. The story is that after my dads car battery died he took the one from my car and got me another. However this "other" battery has turned out to be a load of rubbish. Its not holding a charge properly. It slowly started to get worse and worse even with the 1.5w charger on it which I got for the exact reason of stopping it going flat. However it failed and I ended up using my booster pack twice to get it started. That for one thing suprised me. How a 17Ah SLA could jump start a 1.9L Diesel. It happily cranked it for 5 seconds before it fired up which I was very glad of. At least I know it can do it now, something I had my doubts about beforehand.

I've had very little sun over the last few days so Ive still not replenished the ~10Ah I took out of it with the laptop earlier in the week. It hit 1A for a few hours today but that will be taken out tonight with the CCFL.

Sunday 13th May 2007:
Wow, Ive been really busy recently. Ive had exams at college so Ive been really tired by the time Ive got home. I haven't done much in the way of RE over the last few weeks but I did observe my meter getting up to 1.82A yesterday! Looks like winter sun is rubbish in the UK. Either that or my panels angle isnt quite right.

I always seem to have a full battery these days. I need to start using it more. Even though my maths says I can only get about 10Ah of power per day from my panels, I seem to be able to use more and still have a full battery that floats at 14.2v for hours on end.

A better story is that I have just got myself a car, but still no insurance. Im going to start planning my split charge system which Im going to install some time before july's camping trip if I can (thats assuming I get insurance before then). This will be used to supplement the solar in charging the 90Ah SLA if it should become too discharged.

Friday 27th April 2007:
I moved the 18w panel that was inside back outside today. I also saw the maximum output I have ever seen from the panels, 1.42A. Obviously this isnt its best and with angle tweaking it would be better, but the problem is that the meter is indoors and the panels are outdoors. Taking a meter outside wouldn't work that well since everything is wired into a connection box. However Im a little more pleased with the output of the panels now.

Ive just added a "12v Items" page to the site which illustrates which 12v items I have to replace their 230v mains adaptors. Hopefully it will be interesting to some people.

Monday 23rd April 2007:
Its been a busy month this month. Since my last entry Ive been away on holiday for a week to a friends house and Ive gone back to college after the 2 weeks easter holidays.

While I was away I set the float voltage to 13.8v (0.3v higher than last time). When I got back the battery was floating on just 40mA at 13.68v. I applied a 0.43A load to it (my CCFL) and it stayed above 13.2v for almost 2 hours, showing just how much of a charge it got while I was away.

Earlier last week, I ran my laptop for almost 4 hours off the inverter to see how well it would cope. It coped really well and Im just waiting for a decent amount of sun to fully charge the battery again. I estimate about 20Ah of power was drained from the battery that night. 2 days of full sun and then very little after that didn't fully recharge it but got it back into the 13v range.

The other day I moved my Amateur Radio gear into the loft because I got a load more equipment from a friend to add to the collection. The desk here in my room isnt big enough for it all so I moved it. Because of that the 7Ah SLA used to run it has been retired for now, so Ive hooked up the 6w panel to the main array to give it that little bit extra power. It added about 80mA of power when there was dull light, the more the better.

Thursday 5th April 2007:
We've had loads of sun the last two days. Today I managed to charge my handheld amateur radio's battery from the inverter without draining the battery at all. 1.03A in and a steady 13.61v at the battery. I would charge it from the mains but with a full battery and 1A of power to burn off, why not use the inverter? Makes sense doesn't it.

I finally put the battery into its nice white box yesterday to make it look a bit neater, and it really did the job. I have a warning sign to go on the top when I get round to laminating it. If I don't laminate it the rain will wash the ink away when Im camping.

Ill be adding pictures of the stand and boxes to the site soon so you can see how it was all made. I still havent finished the panel stands yet but I only need something to make the feet out of and some bolts to hold the panels onto it. Apart from that it is finished.

Friday 23rd March 2007:
Its been dull the last few days but the battery has still been getting a good charge by the time I get home. On Wednesday I got the rest of the portable stuff done to the extent where it just needs sanding and painting. I now have all three parts nearly completed. The battery box, the solar panel stand, and the monitor box.

The battery box just needs sanding and painting before it is complete. I also need to find some polystyrene to put into it as an insulator but thats not a necessity.

The solar panel stand just needs a few matching screws and the holes drilled for the mounting of the panels before its finished. As an addition Im going to get something to use as feet to use tent pegs when camping. This will ensure the wind doesnt knock it over.

The monitor box is completed. I just need to mount the stuff onto it and wire it up.

I should have this done over the weekend hopefully and by the end of it I should have some pictures to put up a page for it all.

Wednesday 14th March 2007:
Finally we are getting some decent sun throughout the day. Almost every day in the last week Ive come home from college to a fully charged battery. Having only used a few Ah per night its to be expected but with only 36w (but about 24w effective with one being behind a window) of solar, its not doing too badly.

Im planning to put some money away to get another 18w panel to make up for the smashed one. I planned on taking 3 camping with me so 3 I am going to take. Im also going to start work on the solar panel stand and the rest of the control box next week. I should get the stand done in a few hours since its only some wood and some hinges. The other box however will take a little time and Ill probably end up tweaking it again from what I decided a few weeks ago.

Ive pretty much decided to remove the inverter from the equation altogether now since I doubt Im going to use it all that much while Im away. Ive got nearly everything onto 12v. My phone, PDA, digital camera and PMR's chargers are all 12v, so that leaves only my friends chargers on 240v. My laptop is also still 240v but I intend to get a 12v adaptor for that eventually as well.

Im still getting nowhere with getting a small wind generator. Ive been looking and thinking but I cant find or think of any way I can easily do it. Buying one is expensive and building one I just don't have the tools to do it so its put me at a bit of a dead end. Im sure Ill work something out.

Tuesday 6th March 2007:
Sorry about the lack of updates. Ive been quite busy recently and I havent had time to update the log.

After a week of no loads and only charge the battery didn't quite reach full. It must have been dull all week because the battery was still on 13.00v when I got back. I did a mains charge for a few hours to bring it back up and its lasted a week and two days now without going below 12.95v. Today it was fully charged and rested at 13.34v.

The high winds are picking up again and I was worried about the single 18w panel on the roof of the shed but it hasnt budged an inch so Im quite happy about that. The gusts are the same as the first panel smash but it seems fine at the moment.

I haven't got any further with the box for all the solar stuff yet. Ive got the battery box made but it needs plaining and painting before its finished. I hope to start the second box for the meters etc and the solar panel stand in a few weeks. The panel stand should be easy and should only take a few hours to make. In the mean time everything is temporarly wired up again like the 17.2Ah setup.

There have been changes to my plans for camping this year. We're not going in May anymore, but we're going in July instead. This is because my friends Dad cannot get time off until July, and its his organised holiday and its not fair to go without him. This means I should get the full portable setup finished but if not, then Ive got the 6w panel and the 17.2Ah SLA. Both setups should be fun to use anyhow. I may even take both with me and let someone else who is camping with us mess around etc and see if I can get them into renewable energy.

Saturday 17th February 2007:
I ran my pc off the inverter for 1 hour yesterday using the 90Ah battery. The voltage dropped to 12.3-12.4 the whole time it was on. As soon as I turned it off it recovered to 12.8v. Seems there is plenty of power in this battery to run me for up to 6 hours! The pc uses 140w maximum so I worked out 6 hours is about right. I haven't mains charged it since then but the solar has brought it back up to 13.26v @ 0.95A so far today (its 12:10pm).

Im going away for a week tomorrow so Ive turned down the float voltage to 13.5v instead of 14.2v. Since I won't be using any power while Im away, I don't want the battery boiling itself away. 13.5v should keep it charged but not overcharge it.

Nothing else to report except that the damaged 90Ah SLA has been repaired sufficiently to use again, but it won't be coming inside the house incase the leak starts again. Ill probably get a trickle charger and keep it in the shed until its needed for something (maybe jumpstarting the car?).

Sunday 11th February 2007:
Not much to report this week except that Ive built the box for the battery, but again more changes to the design. My Grandad and I decided the inverter in with the battery would make the box too big so we changed it back to the way it was going to be before, but this time there are two boxes, battery box and control box. The control box will also contain the inverter, but not open, it will be closed inside the box with just openings for the fan and the plug/switch.

Ive just temporaly hooked up the 90Ah SLA to my system and removed the 17.2Ah. I will be using this battery still however. I might replace it with the 7Ah for my radios. The 7Ah can then return to its old job of powering my RC cars starter box.

We havent had much sun this week so my 17.2Ah SLA was severely discharged yesterday and left me no option but to mains charge it. Hopefully the 90Ah wont need charging by mains quite so often.

Sunday 4th February 2007:
We've had some great sun over the last few days and its been nicely floating my battery (17.2Ah) every day by lunch time, so thats pleased me. Ive still got one panel indoors and one outdoors. Id like to keep it this way until I get a proper mount. I can't afford another panel smashing. Im going to start putting money aside for new panels now. Every 7 weeks I should be able to get a new one if I put 10 away per week. Seems like a good idea.

There have been a few changes in the battery box idea. This new 90Ah SLA is very large in comparison to what I was going to get (33Ah). Because of this its made the design quite difficult. In order to make this box now, its going to be changed slightly. What I intend to do is mount the inverter and battery in one box, and make a smaller box for the charge controller, meters and cigarette sockets. This should make the setup easier and reduce the need for such a large box as I first intended. This could have its complications however. Wiring becomes the hard part, but I think I have thought of a good idea to solve that one.

A few days ago I found some nice plug and socket set at maplin's and I thought they would be ideal for connecting the panels up, instead of using connection blocks, screw driver and slowly taking off more and more of the original cable it came with. It will also make a better connection increasing reliability. Reliability is currently a must considering how little solar I have. I need all the power I can get.

Ive been having more and more ideas for a wind generator but I just cant put any into practice just yet. I want something small scale but which can provide a good amount of power. Because of my now increased battery capacity I have to aim for a higher average output of about 25w per hour (approx 50Ah in 24 hours) to keep up with the current demand I place on the system. As I get more power Ill be increasing this demand but thats something else to worry about in the future.

Thursday 25th January 2007:
I got the 90Ah SLA on Tuesday but yesterday I found it had a crack in it and was leaking the gel/acid. It was caused by impact damage by the courier. I have taken photographs and sent them to the eBay user I bought it from, and he said he will replace it no problems. He will get in touch with the courier to claim on the insurance for the damage. I should get the replacement next Tuesday.

My new charge controller hasnt arrived yet but I was advised to wait 5 working days befor complaining. Its day 3 today so Monday will be day 5. Ill e-mail the eBay user on Tuesday if it hasn't arrived.

Ive updated the shoutbox code so it now e-mails me whenever someone posts a new message. That way Ill be notified almost instantly of the new message so I can reply if needed.

Monday 22nd January 2007:
Ive ordered the new 90Ah battery and a new charge controller and they should arrive this week. Im looking forward to this because it means my system is matched to the power I can put back in. The lack of solar at the moment isnt helping though but the new charge controller has a State Of Charge meter on it and an Ah meter on it. This is useful so I know how much Im using and how much has been used. Unlike my current setup which is just a few multi-meters, I hope this one will be more accurate.

As soon as the battery arrives I can continue building the box to house everything neatly. The only problem Im going to have is the weight of the battery, which is 28KG. I need to make it strong enough to hold this battery and Im having my doubts as to weather this will be possible with ease.

I have been getting about 0.6A maximum from the solar since one of them smashed. One 18w panel is still in the house and the other remaining one is still on the roof and still lying flat. The 6w panel is connected to the 7Ah battery. It was overcharging on Saturday. I knew it was because the voltage was at 15.5v and I could smell a faint rotten egg smell which means its been venting. As soon as the new charge controller comes Ill be putting the existing charge controller onto that setup, hopefully with the old charge controller box. It should make the setup a bit neater.

As you can see Ive made a few little changes to the site. I hope it makes your viewing experience a little easier. I changed the colour of the nav bar since I started to realise that black was quite difficult to see. I also made some of the site a bit more graphical. I think it looks nicer and more appealing this way.

Keep the comments coming. Ive replied to a few in the last few weeks. I hope the reply I gave was useful to those who did post.

Wednesday 10th January 2007:
Well, it was bound to happen. One of the 18w panels has fallen and smashed (pictures on January 2007 link on the nav bar). There is no output from it in any light. Its not so bad though, its not like ive lost money since it was the first 18w panel that I bought, the one that broke and I managed to fix with a bit of soldering. I did get a free replacement for it so I still have my moneys worth. I paid for two panels, got three and now one is smashed Im back to the two I paid for.

Im now down to 1 18w panel on the roof still laid down with wood on top of it and 1 18w panel in the house against the window. Itll put out about 350mA in full sun through the glass so its got some use at least. I don't want to have to shut the RE system down because of a little mis-hap like this.

Im currently thinking of easy ways to mount the panels on the roof but in such a way that it doesnt cause damage and in such a way that they can be easily taken down when needed for camping. I just passed my driving test today so Im all ready for the driving. I just need the car!

The panels have, built into the frame, a way to put clips or bolts onto it so no drilling is required. This is extreamly useful because its now solved my portable stand problem with mounting them. I now no longer need the wooden supports. I can bolt them directly to the frame. Now, thinking about this, the frame of the panel will act as the "-" in the A frame so two bits of hinged wood and a bit of string/strap to stop it opening out, and the feet to put pegs through will do. The perfect plan! Now to put it into action!

Wednesday 3rd January 2007:
I hope everyone had a good Christmas and New Year. I had a quiet one this year. Ill make it more worthwhile next year though!

Ive been trying to run my main laptop from the system the past few days but it doesn't seem to like it. If I leave it idle long enough, and the backlight turns off as Ive set it to, the backlight won't come back on again unless I go into standby and back on again. It seems to be a problem regarding the voltage drop from the normal supply it usually takes, which is 19v.

Ive also been running the RE Laptop from the system a bit too. It handles it really well so Im pleased. I can't wait to use it for real when we go camping again later this year. Im hoping Ill have a car by then so transporting this lot won't be much trouble. If I don't, or I haven't been driving long, then I might stick to the 6w panel and the battery pack again. Im sure I can do without one more time.

I plan to go camping a fair amount this year. It will give me some great leisure time and a lot of time to effectivly test the solar panels in good sunlight, and in a spot where I can easily move the panels and. I suppose in general its just going to be good tinkering time.

In the next few days I hope to order the new 90-110Ah battery. Ive been looking at a 90Ah SLA battery which I feel will do the job. The listing says it can do 1000w for 1 hour, 500w for 2 hours, etc. Seems reasonable. I don't know as of yet what the cycles I can get out of it is but as I won't be draining it too much, it should last a long time. My solar can make about 15-25Ah of power per day, depending on conditions and exposure time. For camping I would assume thats plenty.

Ill also be making the solar panel stand and box for the gear this year. I can only make the box once I have the battery though, since it mainly revolves around that. The stand however simply requires one of the big panels to be taken down for measurements, and thats easy enough done any time.

I can tell this is going to be a fun year!

Saturday 23rd December 2006:
A few days ago I disconnected the 6w panel from the main array and re-used the old cable I had for the array before the 13A cable went in. Im now using it to charge a 7Ah SLA battery so I can power my radio equipment seperate from my main battery and array. I have no second charge controller so the 6w panel is directly connected with just a diode in the way to stop back-flow. Hopefully 6w isnt enough to overcharge it. Since I use it a little every day, the few Ah of power it can replace every day shouldn't allow for overcharging if I use the radio a fair amount.

Ive posted a page with the info on the radios on the site so you can see how it was all set up.

Merry Christmas everyone, and seasons greetings to those who don't celebrate Christmas.

Saturday 16th December 2006:
I tested my other laptop on 12v today. I could do this since I fixed the power socket on it, so now it doesnt randomly turn on and off when you wiggle it.

Its specs are:

AMD Athlon Mobile 2600+ @ 2.0GHz

Here are the results when running on 12v:

Standby Current: 0.01A
Idle Current: 1.67-1.78A
Full Load Current: N/A (I didnt test this today) Update: Tried testing it but when the voltage dropped below 12.30v the laptop cuts off.
Low Battery Cutoff: 12.30v (seems to be random at around the 12.30v mark)

Its not too bad if I use it on the lowest CPU setting (398MHz) all the time instead of 2.0GHz or Automatic Stepping (which changes it depending on load). Also setting the backlight to minimum decreases the current by 0.2A compared with it being on maximum.

Friday 8th December 2006:
Ive started running my Amateur Radio equipment from my RE setup. On receive its current draw is 0.09A so it will last a very long time. On 10W transmit it draws around 2A, and 30W transmit it draws about 5A. Ive recently decided to get back into the hobby after over 1 year off-air with only brief times on-air.

Ive still left the panel down but the winds seem to have dropped a lot recently so I might put it back up tomorrow some time. The extra power will come in handy.

Monday 4th December 2006:
Well the panel that fell last time has fallen again. Ive decided to just leave it because it is only going to blow down again and again with these stronger winds.

Didnt quite charge the battery today. It has been dull since lunch time so that doesnt suprise me.

I started installing some software on the RE Laptop. Word was the main program to install because its the program Ill be using to do all of my "journal" stuff on. Ill also be taking pictures while Im camping and adding annotations to them. Unfortunately I don't have any way to get the files to the laptop. There are no USB slots on it so I can't use that. I could try infra-red and use my PDA to send them but it is painfully slow. Either that or just grab the image number and use that in the annotation, then when I get home I can transfer it across.

Ill soon post a page on the RE Laptop so you can have a look at what its like. I hope you enjoy it!

Saturday 25th November 2006:
One of the panels fell over on Thursday in the wind. It didnt break thankfully, and it landed face up so its still giving some output. I havent' had chance to go and put it back up yet. Its been raining and windy since Thursday evening. Sods law says Ill put it back up and it will blow down again tomorrow so Im going to wait until its dry and the wind is calm.

The battery is sitting at 13.22v at the moment, green light says its charged. It hasnt even been through absorbsion yet so it can't be charged. A new charge controller is on my list of things to buy after Christmas.

Saturday 18th November 2006:
I got a spectacular 1.7A from the panels today then suddenly it dropped to 1.05A. The sun hadnt changed it just suddenly dropped. Im guessing that means a panel is intermittently working and just when I thought everything was OK...

My new box for the battery and control panel is coming on nicely. I got the wood this week but we're having to make some adjustments to the measurements. We mis-judged how big it was actually going to be, now its too big!.

Saturday 11th November 2006:
Not much has happened recently except the extrodinary 1.25A I was getting today! Its a lot better than it was last week. It has to be the winter sun causing this, it can't be anything else.

Im charging the battery on a 13.8v regulated charger overnight tonight. It should give it a proper absorbtion charge, something its not getting on the solar since the charge controller is only cheap. Although the charger is 13.8v regulated, its keeping it at 13.88-13.90v. Im guessing its only regulated under a good load, and as the battery is just about charged, there isnt much of a load.

Monday 6th November 2006:
I havent really done anything RE related in the last week or so. I was considering abandoning RE altogether because I am unable to get the best from my panels where they are located. My Dad won't let me put them on the roof because of not being able to find a way of mounting them properly, securely and so it doesn't look like an eye-sore, which is his main concern.

I took the battery down to 0% the other day charging 12AA batteries. That sucked 9.2Ah from the battery, plus the light took another 3-4Ah, and it probably wasnt fully charged anyway. That left me with 10.9v under load. I put it on a mains charge overnight so I didn't damage it too much. That seemed to be good because its showing a better charge at the end of the day now.

Tuesday 31st October 2006:
My battery is starting to struggle with the short days and long nights now. Because Im running the light for longer than normal (about 6-8 hours per night) the solar is barely keeping up. Today I had a charged voltage of 13.03v, which isnt quite full.

On a better note, my Dad has agreed to consider putting the 3 18w panels onto the roof of the house, "IF" we can find a way of mounting them without damaging the tiles or making the roof leak. Im excited now because it will mean the angle is fixed, instead of the panels falling and being random when I put them back up, and also they will get longer sunlight since they will be higher up and not obstructed by houses/trees in the early morning/late afternoon. I may finally get the 60w the panels are rated for!

Friday 27th October 2006:
After being away for a few days Ive come back to a nicely charged battery. It has sat here most of the day floating on about 40mA, currently 13.72v @ 40mA (2:15pm). Its currently totally overcast hence why the current is so small. Usually the charge controller would have cut off to zero charge current but since there is hardly any current it hasnt gone over 14.2v yet so it hasnt turned off.

Im planning on getting a small wind generator soon. Im looking to aim for just 10w average output over each 24 hours. Since solar isnt exactly abundant in winter, but wind is, a small 10w generator will easily keep the battery charged. 10w for 24 hours is about 18Ah, 15Ah if you take into account the inefficiencies. I only use a few Ah a night, so you can see how easy it will be. It should also allow me to run more from the system with a continuous 10w of power. I may never even run the battery down at all with the light if im putting out 10w with the wind generator. The hard task now is finding or building a small generator.

The laptop I converted last saturday doesnt like a voltage under 12.00v! After the voltage drops down below 12.00v it crashes and wont respond, obviously due to the lack of voltage required to run it.

Saturday 21st October 2006:
Yesterday I converted an old 166mhz laptop to 12v power instead of its original 18.6v supply. Because of the lower voltage the laptop will always try and run from its internal battery unless removed, and it will not charge it. The power usage is about 15-27w (1.2A - 2.2A) depending on what the laptop is doing, which isnt too bad. Im hoping I can take this camping with me to keep a sort of log of what ive been doing and also to continue this RE log.

Tonight Ive drained the battery to 12v again with using the 166mhz laptop but this is just a test really.

On another note, I saw 1.6A from the panels today so Im guessing its the cloudy haze thats preventing the panels from working properly. I read somewhere yesterday that even the slightest haze can reduce the output significantly. Lets hope its right and that the panels are working properly.

Monday 16th October 2006:
Over the weekend I installed the diodes to each panel in the hope it would help increase the output a bit by not allowing backflow. Unfortunately its not that much better and Im still only getting 1.2A max into the battery despite 2.2A+ short circuit current. Im beginning to suspect the battery since it lasted 15 minutes with a 100w load on the inverter on Sunday, which is pitiful considering my UPS with a 7AH SLA will run it for 20-25 minutes. Although having said that the cut off voltage on my UPS might be lower than the 10.5v of the inverter.

Also, another one of the 18w panels broke, but I was able to fix. It is for the same reason as the first one that broke, the wire came off inside the connection box and needed to be resoldered. This one was somewhat easier though as the ribbon to the panel was still pretty much intact.

Wednesday 11th October 2006:
I fitted the cable earlier but I havent been able to test it because it was nearly dark when I had finished. It did manage to light 5 white LED's though which shows some power is flowing.


I drew the battery down to 11.9v under load last night charging AA batteries on my new 12v AA charger. Thats the lowest Ive ever taken the battery but it seems to be back up to 13.25v already from the solar (at 2pm, 310mA into the battery).

I still havent fit the new cable as I don't have the time, or the weather is bad when I do find time to fit it.

Sunday 8th October 2006:
Ive been checking the ammeter throughout the day on the 60w array and its reached 0.8A total even in total 100% direct sun. It seems the resistance in the cable is taking its toll. Luckily I have the new cable here ready to fit. I just need to find time to do it. Its going to get wired properly this time and the heavier guage cable will allow all the power to be harnesed and not wasted in heat.

Im still looking for a new battery too. 33Ah isnt what I had in mind for my system but at the moment it seems its the best match. I could also parallel it with the 17.2Ah for a total of 50.2Ah.

Last night the battery went down to 12.43v. Because its coming in dark earlier as each day progresses Im ending up using the light earlier, and longer, so therefore Im using more power than usual. When the rewiring is done and I get a new battery this wont be much of an issue, but 12.43v is over what I would normally turn the light off at. 12.4v is 75% SOC according to the SOC chart.