May/090
The Cheap, All-In-One Solar PC. iUnika Solar Announced.
Does this mean goodbye to my solar panel, my 1KG lead-acid battery and the box full of cables I have? Does these mean that you won’t have to spend over $1000 on a Solar UMPC kit now?
iUnika have announced a range of very low end, low-cost netbooks which include one with a solar-panel on the back. The price: $260.
- 700gm
- 8″, 800×480
- 400Mhz MIPS CPU
It’s eco friendly too “..the system body’s is made from bioplastics and other biodegradable materials derived from starch and cellulose” [source]
Here’s my take. Using a PC in the sun is hard work on the eyes and hard work on the battery as you need to pump up the backlight. The solar panel is also very small (I estimate 4W max output) so with a device that’s likely to be in the 3-4W operating power range, it’s at best, a trickle charger that can keep the device topped up when not in use. Putting panels on PC’s does a nice job of cutting out the losses you get when charging external power banks but they need to be detachable to get the best use out of them.
Still, bravo to iUnika for doing this. There are definitely some customers that would benefit from this. Education in hot countries with poor infrastructure comes immediately to mind.
Source: Gearlog
Jul/082
Spot the difference. (Technology moves on)
One year ago (see this post for details of the 2007 Solar UMPC tour kit,) I was using the setup below for my mobile blogging and tracking.
This year, its a lot simpler. And a lot more powerful. Notice how the phone, GPS tracker and Camera have merged into one device. Yes, the N82 is a real boon. The N82 camera is not as good as the S2 (as expected) but the ability to auto-tag while tracking and then post the images directly to a server over the Internet is a massive advantage.
You’ll also notice a change in UMPC. I’m now using the Samsung Q1 Ultra (with XP and HSDPA) which has an SD slot (negating the need for any cables for the camera) and a much brighter, higher resolution screen. I’ve also moved to SSD rather than the traditional, spinning hard drive. Its safer. The keyboard (A Samsung Q1 keyboard) remains the same as there’s still nothing out there that can beat it. You’ll also see the USB LED lamp. Still, a key part of the kit!
Now lets look at the solar setup. This is the setup I used a year ago.
And this is the setup i’m going to use over the next four days while I go work/camping.
[The Wife and Kid are off camping together and I was due to stay home and work but I've decided to come along and make a working holiday of it. Dads - this is the beauty of Ultra Mobile PC's!!!]
I’ve removed the lead acid battery from the kit and am now direct charging the Tablet Kiosk MP3400. It only charges during peak hours (one full charge per 100% sunny day here in mid-summer Germany) where the SLA battery charges during less sunny periods but the amount of energy you get in those few extra hours is minimal. I’ve chosen to drop the SLA battery and use the MP3400 direct on the Sunlinq 25W solar panel.
Here’s a post with more detail about using the two together. And a how-to video.
I’ll probably post a few solar computing thoughts while I’m away so stay tuned here for more. Weather is looking good!
Last year on the Solar UMPC tour.
Aug/072
Berta the Blue Bakers Bike
Distance since lost post: 15km
Weather: Clouds thinning
Notes: I don’t have much faith in the lead-acid battery. The Li-Ion battery seems to be charging much more reliably.
Another day completed and I feel like I’m getting into a better rhythm. Checking emails and RSS on the mobile phone and creating rich journal updates with the Q1b. I only wish I had a mind recorder because I’m thinking of some great ideas while I cycle but forgetting them when I get to a point where I could write them down!
The bike, which I’ve decided to call Berta (the Blue Bakers Bike) is performing fantastically well. I was a bit worried about having no gears but the fixed gear ratio is perfect for around 22km/h which, with 65KG of pack on a 25KG bike is just perfect. The thick tyres help to soak up bumps and now that I’ve pumped up the pressure a bit more, seem to roll without too much resistance. I even clocked 34kn/h on a straight today . Wohoo! Berta is Berta
Tomorrow morning I will cross the Rhein on a ferry over to Bingen, a lovely town that I’ve visited before, and then continue up the left side of the Rhein. The hills meet the rive here and so there could be an issue with mid-afternoon sun dipping behind the hills. If that’s a problem I’ll switch sides again but I can see from my map that the route on the other side takes me up into the hills. Not good!
Time for some sleep now. I had yet another good meal and feel like I’ve capped a good day!
Aug/070
Winter is coming.
Distance since last post: 40km
Weather: Mixed, cloudy. Hazy. Warm 20-22 degrees
Notes: Feeling really good. No aches. Pushing harder today. Cant stop eating sultanas! The hills on each side of the Rhein are getting bigger!
Winter is coming…If you take notice of the geese that is. I saw a flock flying south (following the River perhaps) this morning and wondered if they knew something that I didn’t. Its was lovely and warm yesterday and its pretty much the same today. Is there some nasty weather around the corner or did they get an SMS from some Geese mates in Africa telling them to come early?
Although its been warm its been very cloudy today. Much cloudier than yesterday and yet I still managed to get some charge into the Li-Ion battery and (I think) something into the lead-acid battery. Despite that though I’m using my spare battery and thinking carefully how to use the UMPC more efficiently. Daytime use (like now!) is not the best as the backlight needs to be turned right up. That’s draining an extra 2 watts compared to evening use when I can drop the backlight to minimum.
I felt very strong this morning and powered the 85KG bike/baggage combo through to Mainz in much less time than I had planned. It was really enjoyable. While the clouds where thick I kept on cycling and ended up in Eltville where the was a lovely Rhein terrace restaurant serving Spargel Suppe (Asparagus Soup.) I stayed for an hour while the solar panel and bike rested by a tree and then layed myself down on a bench for an after-lunch nap. After buying, writing and sending a few postcards I carried on the journey. The Rhein-side path was pretty bumpy and at every chance I tried to find another route but this was really the only sensible offering, the other being a trek up to the hills! Then, after about ten minutes I heard a crash behind me and stopped as quickly as I could. I looked back to see the battery packs and cables strewn across the path along with the shattered container. Shit! I gathered it all together, repacked it and then checked everything out.I think I’ve been lucky. Everything seems to be working still so I think it was just a warning from above to tell me not to take afternoon naps!
Only about 20km to go until the campsite and having looked closely at my plan, it appears that I’m ahead in terms of distance but behind in terms of energy capture. I need to take longer breaks. But no afternoon naps!!
Aug/070
Tour day-plan.
Planning a busman’s holiday around the weather isn’t that easy. Camp set-up and break down, cycling between locations, working, keeping an eye on the weather, finding suitable places to work and charging power sources all need to be thought about. The key to success here (in our wonderfully changeable weather system) is to be flexible between 10:00 and 16:00 when there’s a possibility to get something out of the sun. Outside these hours there isn’t enough power in the sunlight to make it worth any effort or planning.
The original plan was to cycle during the day with the solar panel across the back of the bike however, a 25W panel is too big to lay in a useful, efficient position across the back of the bike so either I suffer with 50% energy loss or I stop when the sun shines. Having thought about it for about 2 seconds I think the latter idea is rather good and in fact, the objective of the tour is not to cycle as far as possible, its to test and learn about how UMPCs can be used and powered in mobile situations.
A rough dry-day plan could go like this.
- 0730-0830 wake up. Check email/RSS, Cuppa, Breakfast and pack up.
- 0845-1100 on the road for a concentrated 40km ride. Panel 50% deployed on bike but not expecting any usable power at this time of day.
- 1100-1600 Weather watch! If its sunny then stop and charge! Work, play, read, eat during this time. If not sunny try to get to campsite before midday in order to deploy trickle charge solution. Best charging period is 1200-1400 here.
- 1700-1900 If not already at campsite, set up tent. Find food. Shower. Food. Relax. Connect mobile phone and AA batteries for top-up from lead-acid battery.
- 1900-2100 Work (max 1.5 hours)
- 2100-2130 Prep for morning.
- 2200-2300 To bed with RSS, emails or book. Pray for sun! Earplugs in (camping by the Rhein is always noisy) and sleep…
Next job is to get the Google map started. I’m using RoboGeo to generate a live route map (here’s one I prepared earlier!) with images but I’d like to merge Google ‘My Map’ KML data with it so that I can build more than just a track map. If anyone has any ideas about this, please let me know.
Update: I worked it out. You can create the My Map in Google Maps by doing the usual drag a nd drop, draw etc etc. Then export the KML. Uload the KML to your web server and add the following two red lines into your RoboGeo ‘map.htm’ file after the ‘var map’ line. Obviously you need to adjust the URL to point to the KML file you uploaded.
var map = new GMap2(document.getElementById(“map”));
var geoXml = new GGeoXml(“http://www.solar-
umpc.com/images/moblog-30-4-07/SolarUMPCTour.kml”);
map.addOverlay(geoXml);
Once you’ve done that, upload the RoboGeo dir to your server and link to the map.htm file.
Here’s one I’ve just made with a previous RoboGeo route and photos and if you zoom out you’ll see the start and endpoint for the tour and the current location of my bike. The great thing about it is that as you update your ‘My Map’ the created map changes too as it pulls in all the data from the Google servers. Wonderful!
I’m now off to do a bit of shopping. Packet soup, sultanas and muesli bars. Yum yum! create some maps!
Jul/070
Xantrec 300 / Sunlinq portable solar solution
Here’s a solution based on the Sunlinq 25w panel and a Xantrec 300 Plus combo lead-acid battery/inverter. Its very similar to my own solution apart from the fact that this one weighs nearly 10KG!!!
A number of blogs seemed to have picked up on this solution today and are quoting 11-12 hours charging time. This figure is a little misleading. The battery capacity is about 240w/hr and based on a reasonable 5-hour per day full-sun rate its going to take 10 hours. That’s a minimum of 36 hours duration! In middle-Europe, you’ll be waiting for 3 full days of sun!
The other point to consider is that you need to take all your AC converters with you (weight problem) and should recon on 20% energy loss by converting from 12v -> 110V and down to 12, 16, 19 or whatever voltage your device takes. Hardly efficient. Alternatively you can buy 12v car adaptors for all your equipment (can get expensive.)
My recommendation is to use a combination of a Li-ion battery with variable DC output (I’m using the TabletKiosk/Tekkeon MP3400) and a lead-acid battery (I’m using a 2.5kg 6Ah part) This gives you the best of both worlds (lead-acid flexibility and Li-Ion light weight) and cuts the total weight right down to under 4KG. At also avoids having to operate a dangerous 110v. Capacity with my solution is around 130W/hr but here’s the key. Don’t use a notebook PC, use a UMPC. They are far more efficient. With a normal UMPC you’re good for 10 hours of computing on a fully charged system (around 7 hours full-sun charge time.)
News Via GottaBeMobile.
Jun/0710
Sunlinq 25W and Tekkeon Power bank work well together.
I don’t really understand why I didn’t try this before. Its simple. its recommended and it works. Have I been too focused on flexibility why simplicity could be the answer?
I was speaking to Chris from Euro-Line, an importer of consumer solar products and he highlighted a document that I’d already seen. I took another look and staring me in the face was a recommended and tested solution using equipment that I already have. Its the same setup that I tested with the P3 panel. Just plug the panel into the Tekkeon MP3400 and wait for enough sun. You might remember back in the early posts that this is how I found out that Li-Ion charging solutions where not so efficient and how it set me on the path to research a more flexible solution.
With the ’12v’ 25w Sunlinq panel I have I assumed that a 12V output wouldn’t drive a 19v input and after looking at the diagram again I though ‘why are they recommending this solution? It shouldn’t work.’
Image taken from GlobalSolar.com PDF here.
Looking more closely at the specs of the panel, its clear now why it works. The 12 panel isn’t strictly 12V. The voltage varies according to the load and in fact with an open circuit the voltage is way up over 20 volts. However, with a load of around 800mA, the charging current for the power bank, the voltage sits nicely at around 20V. Tada!
With a 25W panel, 800ma at 19V is reached at around 60% sun power. On a clear summer day here, the sun is over 60% power for around 5 hours between 11 and 4pm. The charger needs 4 hours to load up 56W of energy.
Now here’s an idea. Between 12 and 2, the panel is producing 40% more energy than the Li-Ion battery is taking. Can I mop that up with a lead-acid battery?
Testing continues…
Jun/071
Solar charging. Lead Acid vs Li-Ion
In a recent comment here, someone asked why the Lead-Acid battery was needed. Its probably not too clear in the video why I use it so I reproduce my answer (which comes from the best of my knowledge!) here.
There are two main problems with charging Li-Ion batteries from Solar panels.
Firstly, Li-Ion batteries (in notebooks and battery bank) charge using a constant current (stream) of power. For common notebook batteries and battery banks such as the Tekkeon MP3400, this is around 1A. A lot of the 12V portable solar panels only reach this power at high sun levels meaning you can only use them for a few hours mid-day. In fact a 12W panel might not be enough to even start the charging process. Secondly, if you have a huge panel that could deliver, say, twice as much power as needed, its not used. Only the power needed is taken. The rest is wasted.
These two problems can be overcome at the expense of weight with a lead-acid battery.
L-A batteries are more flexible. You can charge them with a trickle and also with a higher charge rate. They are much more suited to pairing with a solar panel. The problem with this solution is weight. Small 12v L-A batteries are over 2KG in weight!
What’s needed is a flexible Li-Ion battery charging solution. Currently there are no products on the market that can archive this but I’m searching hard!
In summary there are 2 solutions.
1 – Get a panel powerful enough to charge a Li-ion battery at 70% of its rated output. For example, a 25W panel and the Tekkeon MP3400 Li-ion battery. This will give you about 4 hours of charge time on a sunny summer day. (Mid-Europe) This should be enough to completely fill up the Li-ion battery.
2 – Go for a heavier solution with a L-A battery and give yourself more charging flexibility.
Jun/079
Video: How to use a solar panel to power your gadgets.
Before I talk about the video I just want to say “where’s the damn weather!” Lesson number one in the Solar-UMPC project is that the weather is chaos and if you live in mid-northern Europe, you can’t rely on it as a source of instant energy. You’ll see how I’ve had to adapt my solution in my first Solar UMPC video. In the video I present the solar charging and storage setup that I’ve decided to use for the tour. Its based on the fag-packet drawing I did a few weeks ago after deciding that Li-Ion batteries weren’t really the best solution.
I’ve introduced the lead-acid battery as a buffer and despite the 100-year old technology and 2.6KG weight, provides the perfect stabiliser to the whole architecture.
A quick rundown of the equipment I’m using (mostly bought from my home country, Germany.)
- Sunlinq 12v / 25W foldable solar panel.
- Sonnenschein 12v / 6.6Ah lead-acid battery.
- Solar charge controller. 12v / 4A
- Samsung Q1b UMPC.
- TabletKiosk MP3400 Li-Ion battery pack.
- Voltcraft dual-mode 12v battery charger.
- Voltcraft 12v DC-DC adaptor.
The 20-min Video is below (800kbps divx, 120MB) and also downloadable here. If you can handle a 1.5mbps stream or 200MB download, take the WMV version from here. YouTube version also below. More pictures in the gallery here. Blip.tv link here for sharing. Many thanks to SelectSolar for their help in preparing this solution.
Now available at YouTube:
Jun/070
An evening outside with a Samsung Q1b.
The new tent has arrived, the bike baggage, and finally, some warmer weather so I’m taking the chance to test things out in the garden. My daughter is nearly asleep in the tent and I’m perched outside with the Samsung Q1b and organizer pack resting on one of my panniers, a clip-on LED lamp a paraffin lamp and a bottle of Germanys best beer!
This is the perfect time to be writing because its dark and you only need the minimum of backlight on the UMPC. As I write this with WiFi on, I’m taking between 6.5 and 8.5W on the UMPC. Its also wonderfully quiet.
Behind me, in the spare bedroom, I have started to lay out everything I need for the tour. I’ve written the pack list and there are only a few more things to buy before I’m ready to go. I hope it all fits into the panniers I bought for the bike which, incidentally, is going to be the blue Kronan.
A few things that haven’t turned up yet are the Lead-Acid battery and the solar panel. They should be here on Monday which will allow me to build the frame that the panel and battery will sit in on the back of the bike. I’ve ordered a could of panel meters too because I want to see what sort of drain each component puts on the panel.
One thing I was a little disappointed to find out tonight is that in theory, DC-DC conversion will cost at least 25% of my energy. That’s rather a lot to be wasting just to transfer energy, especially if I charge the Li-Ion battery from the 12V lead acid battery. I could lose an hours computing time just in that process.
I’ll finalise the packlist (V1.0) in the next few days and post it up. I’m also planning to do a video overview of all the equipment I’m taking, a picture-set of the bike and the charging setup and as many other images as I have time to take. The 9-day forecast is looking OK (not perfect, but OK) and so I’m quite confident that the tour will start at some point next weekend.