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	<title>Solar Computing &#187; power</title>
	<atom:link href="http://solarumpc.com/tag/power/feed/" rel="self" type="application/rss+xml" />
	<link>http://solarumpc.com</link>
	<description>Solar, Ultra-Mobile and Eco-Friendly Computing</description>
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		<title>Taking the iPhone off the power grid.</title>
		<link>http://solarumpc.com/2008/12/13/taking-the-iphone-off-the-power-grid/</link>
		<comments>http://solarumpc.com/2008/12/13/taking-the-iphone-off-the-power-grid/#comments</comments>
		<pubDate>Fri, 12 Dec 2008 22:56:00 +0000</pubDate>
		<dc:creator>Chippy</dc:creator>
				<category><![CDATA[Uncategorized]]></category>
		<category><![CDATA[G Smartphones]]></category>
		<category><![CDATA[iPhone]]></category>
		<category><![CDATA[Kevin]]></category>
		<category><![CDATA[Kevin Tofel]]></category>
		<category><![CDATA[mains power]]></category>
		<category><![CDATA[Philadelphia]]></category>
		<category><![CDATA[power]]></category>
		<category><![CDATA[solar cell area]]></category>
		<category><![CDATA[solar unit]]></category>
		<category><![CDATA[Solio]]></category>

		<guid isPermaLink="false">http://solarcomputing.carrypad.com/2008/12/13/taking-the-iphone-off-the-power-grid/</guid>
		<description><![CDATA[Kevin Tofel, an eco-friendly blogger at the excellent mobile-focused website JKOnTheRun has bought himself a solar-powered battery-pack and plans to run his iPhone for as long as he can without connecting it to the mains power. The charger is a Solio Classic with a 6wh capacity cell. The iPhone has a 5wh cell. At first [...]]]></description>
			<content:encoded><![CDATA[<p><a href="http://lh6.ggpht.com/_d7aCR2eLFsQ/SULsJXAGyrI/AAAAAAAAAM0/UMxr7NQGgdc/s1600-h/iphonesolar%5B5%5D.jpg"><img style="margin: 0px 10px 0px 0px" alt="iphonesolar" src="http://lh5.ggpht.com/_d7aCR2eLFsQ/SULsJxWn_0I/AAAAAAAAAM4/YP5qgUr5TS4/iphonesolar_thumb%5B3%5D.jpg?imgmax=800" align="left" border="0" width="161" height="260" /></a>Kevin Tofel, an eco-friendly blogger at the excellent mobile-focused website <a href="http://www.jkontherun.com/2008/12/im-taking-my-ph.html">JKOnTheRun</a> has bought himself a solar-powered battery-pack and plans to run his iPhone for as long as he can without connecting it to the mains power.</p>
<p>The charger is a <a href="http://www.solio.com/charger/explore-solio/what-is-solio.html">Solio Classic</a> with a 6wh capacity cell. The iPhone has a 5wh cell. </p>
<p>At first glance it seems like too much of a challenge. Looking at the solar cell area and comparing it to my own 25W panel which measures about 1m squared tells me that this device is going to have a tiny sun-capture capability. Looking at the FAQ on the device gives a few clues:</p>
<blockquote><p>It takes 8-10 hours to fully charge a Solio from the sun. With peak charging times between 10am and 2pm, it takes a minimum of 2 days to fully charge a Solio.</p>
</blockquote>
<p>8-10 hours for a 6Wh battery is under 1W of solar capture, under ideal conditions.</p>
<p>It&#8217;s winter in <a href="http://maps.google.com/maps?f=q&amp;hl=en&amp;q=Philadelphia,+Pennsylvania&amp;sll=50.705787,7.09717&amp;sspn=0.008058,0.022745&amp;g=Philadelphia,+Pennsylvania&amp;ie=UTF8&amp;cd=1&amp;geocode=FRedYQIdYBeF-w&amp;ll=36.031332,-21.269531&amp;spn=80.101028,186.328125&amp;z=3&amp;iwloc=addr">Philadelphia</a> right now so I guess we&#8217;re looking at an average 60% sun-power through the peak hours which means it will take about 3 average days to charge the solar unit. Taking into account that about 20% power will be lost on cross-charging I&#8217;d estimate that Kevin is going to struggle to get a full charge every three days.</p>
<p><a href="http://lh3.ggpht.com/_d7aCR2eLFsQ/SULsKeyzhTI/AAAAAAAAAM8/auaneF90zV4/s1600-h/smartphoinebattery%5B12%5D.jpg"><img style="border: 0px none" alt="smartphoinebattery" src="http://lh4.ggpht.com/_d7aCR2eLFsQ/SULsKnKLExI/AAAAAAAAANA/SDLJOVK4tKo/smartphoinebattery_thumb%5B10%5D.jpg?imgmax=800" border="0" width="416" height="211" /></a> </p>
<p>2.5G Smartphones like the first-gen iPhone that Kevin has, can easily take 2W of power when driven hard. So if Kevin isn&#8217;t careful. he&#8217;s going to be out of power in the first day but it looks like he&#8217;s done his research and is well on top of the challenge&#8230;</p>
<blockquote><p>The strategies&#8230;let me go two days without charging my iPhone however, and that gives me two days to capture sunlight with the Solio. I guess if we have a three-day rainstorm, I&#8217;m out of luck. </p>
</blockquote>
<p>The interesting part of the experiment will be to see what type of usage Kevin gets out of the device. Will it be voice only? Will he be able to use regular email polling as he&#8217;s planning. Will he use it as a mobile internet device or just as a voice phone?</p>
<p>It&#8217;s clear that this isn&#8217;t the best way to save energy given that the $75 Euro initial costs that could power an iPhone non-stop for about 40 years (*1) but these sort of experiments, this sort of publicity and the resulting discussion is exactly what&#8217;s needed to stimulate development and improvement of consumer solar solutions.</p>
<p>I don&#8217;t get many readers on this blog but from the responses I&#8217;ve had over the last year or so I know that many of the readers here will have already thought about this. Perhaps you&#8217;ve already done it? If so, what devices did you use and how did it / does it work out for you?</p>
<p>Track Kevin&#8217;s progress at <a href="http://www.jkontherun.com/2008/12/im-taking-my-ph.html">JKOnTheRun.</a></p>
<p>(*1) Assuming the iPone takes a (very high) average drain of 1W, $75 would buy something in the order of 500kwh of household power. With an AC adaptor efficiency of 80%, the $75 over 45 years of iPhone usage.</p>
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		<slash:comments>5</slash:comments>
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		<item>
		<title>Emergency Computing for the Masses.</title>
		<link>http://solarumpc.com/2008/10/26/emergency-computing-for-the-masses/</link>
		<comments>http://solarumpc.com/2008/10/26/emergency-computing-for-the-masses/#comments</comments>
		<pubDate>Sun, 26 Oct 2008 11:37:00 +0000</pubDate>
		<dc:creator>Chippy</dc:creator>
				<category><![CDATA[Uncategorized]]></category>
		<category><![CDATA[emergency]]></category>
		<category><![CDATA[France]]></category>
		<category><![CDATA[G. Its]]></category>
		<category><![CDATA[Internet]]></category>
		<category><![CDATA[mobile internet devices]]></category>
		<category><![CDATA[power]]></category>
		<category><![CDATA[power storage]]></category>
		<category><![CDATA[simple self]]></category>
		<category><![CDATA[V DC]]></category>

		<guid isPermaLink="false">http://solarcomputing.carrypad.com/2008/10/26/emergency-computing-for-the-masses/</guid>
		<description><![CDATA[When I did the Solar UMPC tour in 2007, it was an expensive job pulling together all the equipment. Foldable solar panels and ultra mobile computers were specialist items and difficult to find. The UMPC alone cost over 1100 Euro and had to be ordered through a specialist. Fortunately, Intel are starting to deliver on [...]]]></description>
			<content:encoded><![CDATA[<p>When I did the Solar UMPC tour in 2007, it was an expensive job pulling together all the equipment. Foldable solar panels and ultra mobile computers were specialist items and difficult to find. The UMPC alone cost over 1100 Euro and had to be ordered through a specialist. Fortunately, Intel are starting to deliver on their promise of consumer-focused, highly efficient Mobile Internet Devices (MIDs)and it&#8217;s looking great for anyone wanting to power a real PC from the sun. </p>
<p><img src="http://www.umpcportal.com/gallery/d/9120-3/IMG_6128.JPG" /> </p>
<p>What was 1KG and cost 1110 Euro one year ago is now less than half the weight, takes half the power and cost a lot lot less. Within 12 months, the price will be down to 50% of what it was a year ago bringing mobile computing to the masses. Take the Aigo MID (see info below) It&#8217;s a full Linux-based PC with keyboard and screen, storage, usb, a camera, wifi, bluetooth and will even be available soon with built-in 3G. Its just 350gm in weight and having looked in detail at test results and asked owners about the battery life, its clear that it&#8217;s running in less than 4W of power meaning you can last twice as long on the same amount of stored power or reduce the size of the (expensive) solar panel and power storage. A huge step forward.</p>
<h4>Survival with the Smallest and Most Efficient.</h4>
<p><a href="http://www.umpcportal.com/gallery/v/solarumpcprep/q1p-tent+051.jpg.html"><img style="margin: 0px 10px 5px 0px" alt="q1p-tent 051" src="http://www.umpcportal.com/gallery/d/4854-2/q1p-tent+051.jpg" align="left" width="113" height="150" /></a>Recently, I have been thinking more about short-term emergency supplies. I usually keep a stock of foodstuffs and water in my cellar along with a radio, small gas stove and a radio but I really think a mobile computer should be part of my survival kit, even if it&#8217;s just for day-to-day &#8216;emergencies.&#8217; From being able to compute when your ISP has problems to being able to walk into the middle of a city without power or communications and instantly set up a WiFi hotsopt or Bluetooth hotspot with a simple, self-contained web-server offering emergency information. From being able to move away from an emergency area with your computer with scans of your important documents to being able to send an e-mail greeting to your mother when you forgot to send a card for her birthday (arguably one of the worst disaster scenarios possible!) </p>
<p>In times of disaster, you need to earn money too. As a pro-blogger (<a href="http://www.umpcportal.com/">UMPCPortal</a>) I would instantly lose 100% of my income if the Internet went down but by having an emergency Internet &#8216;station&#8217; I&#8217;d have a lot of possibilities. Can you imagine how much bartering power you would have if your were one of the only people left in your area with a working PC and a 3G connection that could send and receive emergency SMS messages from the cellular radio system! </p>
<p>In times of comfort and stability it sounds almost extreme to be thinking about such scenarios but in the western world, we live in a just-in-time economy. Like the weather, everything could change in 48hrs. Considering your electronic storage, communications and computing as part of your survival kit is is something many people will be doing and having the lightest and most efficient kit is obviously the best way to go. Thank goodness for Mobile Internet Devices!</p>
<p><strong>Solar UMPC Tip of the moment: (click on the links for information from the UMPCPortal database)</strong></p>
<p><a href="http://umpcportal.com/products/Aigo/MID"><img style="margin: 0px 0px 5px 5px" src="http://www.umpcportal.com/gallery/d/13265-4/aigo.jpg" align="right" width="100" /></a><a href="http://umpcportal.com/products/Aigo/MID">Aigo P8860 -</a> One of the first consumer-focused Mobile Internet Devices based on Intel&#8217;s Atom processor and Moblin, Linux-based operating system. Currently available by import. <strong>Average power drain (in-use) under 4W</strong>. 5V DC input. Micro-SD port. Wifi, Bluetooth and USB port about to take external peripherals. Also available in France as the <a href="http://www.umpcportal.com/products/SFR/Mi%20PC%20Pocket/">Mi PC through the carrier SFR</a> and expected to be launched under the Gigabyte brand soon as the <a href="http://www.umpcportal.com/products/Gigabyte/MID%20M528/M528">M528</a>.</p>
<p>Is anyone reading this considering a mobile PC as an essential item in their emergency kit? Is anyone even considering some form of fallback scenario?</p>
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		<item>
		<title>Solar-UMPC-powered web server testing.</title>
		<link>http://solarumpc.com/2008/05/06/solar-umpc-powered-web-server-testing/</link>
		<comments>http://solarumpc.com/2008/05/06/solar-umpc-powered-web-server-testing/#comments</comments>
		<pubDate>Tue, 06 May 2008 10:12:00 +0000</pubDate>
		<dc:creator>Chippy</dc:creator>
				<category><![CDATA[Uncategorized]]></category>
		<category><![CDATA[arm architecture]]></category>
		<category><![CDATA[Europe]]></category>
		<category><![CDATA[Everun]]></category>
		<category><![CDATA[measurement tools]]></category>
		<category><![CDATA[panel]]></category>
		<category><![CDATA[power]]></category>
		<category><![CDATA[raon digital everun]]></category>

		<guid isPermaLink="false">http://solarcomputing.carrypad.com/2008/05/06/solar-umpc-powered-web-server-testing/</guid>
		<description><![CDATA[Yes, its that time of year again where we get the first encouraging days of sunshine in Europe so I&#8217;ve been into the cellar and dusted-off my Sunlinq 24W solar panel. &#160;Sun strength for the last 2.5 days. &#160; I&#8217;m not planning a solar-umpc tour this year but I am planning to get some use [...]]]></description>
			<content:encoded><![CDATA[<p>Yes, its that time of year again where we get the first encouraging days of sunshine in Europe so I&#8217;ve been into the cellar and dusted-off my Sunlinq 24W solar panel.</p>
<p align="center"><a href="http://www.solar-umpc.com/files/images/TheSolarpanelisupandrunningagain_13D99/image.png"><img height="171" alt="image" src="http://www.solar-umpc.com/files/images/TheSolarpanelisupandrunningagain_13D99/image_thumb.png" width="402" border="0"></a>&nbsp;<br />Sun strength for the last 2.5 days.</p>
<p>&nbsp;</p>
<p>I&#8217;m not planning a solar-umpc tour this year but I am planning to get some use out of the panel. At the moment, the plan is to run a UMPC from the solar panel that could serve this blog. I doubt i&#8217;ll be able to do it 24/7 for the whole of summer but I&#8217;m running some tests on the <a href="http://www.umpcportal.com/products/product.php?id=110">Raon Digital Everun S6S</a> at the moment to see exactly how much I could get out of it with the 24W panel.</p>
<p>The Everun, when configured for 400Mhz with WIfi and screen off, will consume a tiny 4W at idle and about 6W at full power which is about as low as you can go with a PC without having to switch to an ARM architecture. I don&#8217;t want to do that because the plan is just to install a basic Ubuntu image, fire up Apache and SSH and serve this blog as a set of static web pages. WIthout Mysql or PHP running it should keep the processor load down to a minimum although i&#8217;m not sure that Ubuntu will be able to switch the CPU into 400Mhz mode. It might have to stay locked at 600Mhz.</p>
<p><a href="http://www.solar-umpc.com/files/images/TheSolarpanelisupandrunningagain_13D99/everunsolar.jpg"><img style="margin: 0px 5px 5px 0px" height="240" alt="everunsolar" src="http://www.solar-umpc.com/files/images/TheSolarpanelisupandrunningagain_13D99/everunsolar_thumb.jpg" width="156" align="left" border="0"></a> At 5W drain, the server would need 120Wh of energy to power it for a full day. With a 24Wh panel I&#8217;m only going to get about 80-100Wh per day on average (using the 4-hours sun/day&nbsp; rule that applies to this part of the world) so at some point, back-up power is going to be needed. The problem is, how can I switch-over to back-up power (or gracefuly switch over to another server.) Switching the servers is OK but getting the Everun to shutdown when it reaches 5% power is impossible under Linux right now. </p>
<p>The Alternative is to shut-down the server between 0300 and 0900 every day and to try and regulate it that way or just keep topping up the SLA battery from other sources when needed. </p>
<p>I&#8217;m going to need a couple of new items for this project though.</p>
<p>1) Power usage measurement tools. I want to feed the data back into the website. Power used, power given by panel, current battery level. Any tips there would be much appreciated. Should I buy a dedicated data logging system with software or are there simpler ways to do this.</p>
<p>2) An ethernet port. The Everun only has a WIfi connection and that would take too much power so I&#8217;m looking at a USB to Ethernet adaptor. <a href="http://www.amazon.com/Networks-SMC2208USB-ETH-EZ-Connect/dp/B000063V08">This one from SMC</a> takes about 150mw which will be fine.</p>
<p>3) Bigger SLA battery. Rather than using the 56whr battery that I have, I should get one that takes about 200wh so that if we have two or three good days of sunshine, I can store the engergy and use it on days where the sun is weaker.</p>
<p>Solar panel positioning is going to be a major problem at my house which is badly oriented for a solar panel. I&#8217;m also a bit worried about loss along the length of cable I will need in order to position the solar panel correctly. </p>
<p>Over the next few weeks I hope to at least have a partial solar-powered web server running but if this blog disappears, you&#8217;ll know what&#8217;s happened!</p>
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		<slash:comments>3</slash:comments>
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		<title>Mathematics, sunburn and how 1.2kw of energy gives you 2 hours of computing.</title>
		<link>http://solarumpc.com/2007/08/30/mathematics-sunburn-and-how-12kw-of-energy-gives-you-2-hours-of-computing/</link>
		<comments>http://solarumpc.com/2007/08/30/mathematics-sunburn-and-how-12kw-of-energy-gives-you-2-hours-of-computing/#comments</comments>
		<pubDate>Thu, 30 Aug 2007 19:25:00 +0000</pubDate>
		<dc:creator>Chippy</dc:creator>
				<category><![CDATA[Uncategorized]]></category>
		<category><![CDATA[50 degrees north]]></category>
		<category><![CDATA[Bonn]]></category>
		<category><![CDATA[Germany]]></category>
		<category><![CDATA[li ion battery]]></category>
		<category><![CDATA[Li-Ion]]></category>
		<category><![CDATA[panel]]></category>
		<category><![CDATA[PC I]]></category>
		<category><![CDATA[PC. Today]]></category>
		<category><![CDATA[power]]></category>
		<category><![CDATA[process]]></category>
		<category><![CDATA[solar cells]]></category>

		<guid isPermaLink="false">http://solarcomputing.carrypad.com/2007/08/30/mathematics-sunburn-and-how-12kw-of-energy-gives-you-2-hours-of-computing/</guid>
		<description><![CDATA[When I did my first tests and calculations about the use of solar power to drive a PC I was quite amazed at the inefficiency of the process and today&#8217;s &#8216;laboratory conditions&#8217; test proves just how much room for improvement&#160;there is. It&#8217;s thanks to devices like UMPCs that this is project is at all possible [...]]]></description>
			<content:encoded><![CDATA[<p>When I did my first tests and calculations about the use of solar power to drive a PC I was quite amazed at the inefficiency of the process and today&#8217;s &#8216;laboratory conditions&#8217; test proves just how much room for improvement&nbsp;there is. It&#8217;s thanks to devices like UMPCs that this is project is at all possible because I really doubt it would have worked with even a &#8216;power saving&#8217; notebook PC. </p>
<p>Today I stayed at the campsite and put the Solar panel and Li-Ion battery through a 3 hours test. Its was a cloudless day with a very thin haze, 22 degrees centigrade and for reference I&#8217;m located at about 50 degrees north and 7 degrees east. The date is the 30th of August which is heading towards Autumn here in Germany. The test was done from 11:00 &#8211; 14:00 and I took the empty Li-Ion battery and charged it with the solar panel for 3 hours. </p>
<p>I estimate that about 1.2KW of energy hit my 7000 cm2 panel with about 660W falling on the Solar cells (3500 cm2). After conversion to electricity it created about 50w/hr of energy. Of that, about 40W was taken by the Li-Ion battery because it only uses a fixed current and voltage. It won&#8217;t adapt to the power available. Due to input voltage conversions and charging losses, this left me with an estimated 30W of energy and after taking this through yet another set of voltage conversions and charging process, left me with a rather poor 18W of power. Of course this is enough for a few hours of work but isn&#8217;t it incredible that so much power is wasted (or rather passed back as heat!)</p>
<p>I spent the rest of the afternoon trying to work out how this process could be improved and I&#8217;ve come up with a list of ideas that could help. I&#8217;ll talk though them in the next post but right now I need to put some more cream on the back of my legs because through all the concentration I forgot about the sun and I&#8217;ve burned the bit right  behind the knee. That&#8217;s going to be really enjoyable tomorrow when I make the 70km dash to Bonn.</p>
<p>Here&#8217;s a diagram I created quickly on the Q1b. Hopefuly it makes things a bit clearer. How would you improve the architechture? </p>
<p><a href="http://www.solar-umpc.com/files/images/Mathematicssunburnandhow1.2kwofenergygi_12CCB/solarpower4.jpg"><img height="474" src="http://www.solar-umpc.com/files/images/Mathematicssunburnandhow1.2kwofenergygi_12CCB/solarpower_thumb2.jpg" width="391"></a></p>
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		<slash:comments>0</slash:comments>
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		<item>
		<title>Solar charging. Lead Acid vs Li-Ion</title>
		<link>http://solarumpc.com/2007/06/27/solar-charging-lead-acid-vs-li-ion/</link>
		<comments>http://solarumpc.com/2007/06/27/solar-charging-lead-acid-vs-li-ion/#comments</comments>
		<pubDate>Wed, 27 Jun 2007 11:08:00 +0000</pubDate>
		<dc:creator>Chippy</dc:creator>
				<category><![CDATA[Uncategorized]]></category>
		<category><![CDATA[A. A]]></category>
		<category><![CDATA[battery]]></category>
		<category><![CDATA[battery li ion]]></category>
		<category><![CDATA[Europe]]></category>
		<category><![CDATA[lead acid battery]]></category>
		<category><![CDATA[Li]]></category>
		<category><![CDATA[li ion battery]]></category>
		<category><![CDATA[Li-Ion]]></category>
		<category><![CDATA[panel]]></category>
		<category><![CDATA[power]]></category>

		<guid isPermaLink="false">http://solarcomputing.carrypad.com/2007/06/27/solar-charging-lead-acid-vs-li-ion/</guid>
		<description><![CDATA[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 [...]]]></description>
			<content:encoded><![CDATA[</p>
<p>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.
<p>There are two main problems with charging Li-Ion batteries from Solar panels.
<p>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.</p>
<p>These two problems can be overcome at the expense of weight with a lead-acid battery.<br />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!</p>
<p>What&#8217;s needed is a flexible Li-Ion battery charging solution. Currently there are no products on the market that can archive this but I&#8217;m searching hard!</p>
<p>In summary there are 2 solutions.<br />1 &#8211; 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.&nbsp; (Mid-Europe) This should be enough to completely fill up the Li-ion battery.<br />2 &#8211; Go for a heavier solution with a L-A battery and give yourself more charging flexibility.</p>
<p>&nbsp;</p>
<div class="wlWriterSmartContent" id="0767317B-992E-4b12-91E0-4F059A8CECA8:e1202b55-3d3b-412b-90bf-20ac28d5a5bd" style="padding-right: 0px;padding-left: 0px;padding-bottom: 0px;margin: 0px;padding-top: 0px">Technorati tags: <a href="http://technorati.com/tags/solar" rel="tag">solar</a>, <a href="http://technorati.com/tags/charging" rel="tag">charging</a>, <a href="http://technorati.com/tags/computer" rel="tag">computer</a>, <a href="http://technorati.com/tags/laptop" rel="tag">laptop</a>, <a href="http://technorati.com/tags/energy" rel="tag">energy</a>, <a href="http://technorati.com/tags/battery" rel="tag">battery</a>, <a href="http://technorati.com/tags/Li-Ion" rel="tag">Li-Ion</a></div>
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		<slash:comments>1</slash:comments>
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		<title>Could Solar Energy solve the UMPC Battery Life Problem?</title>
		<link>http://solarumpc.com/2007/06/14/could-solar-energy-solve-the-umpc-battery-life-problem/</link>
		<comments>http://solarumpc.com/2007/06/14/could-solar-energy-solve-the-umpc-battery-life-problem/#comments</comments>
		<pubDate>Thu, 14 Jun 2007 08:48:00 +0000</pubDate>
		<dc:creator>Chippy</dc:creator>
				<category><![CDATA[Uncategorized]]></category>
		<category><![CDATA[efficiency level]]></category>
		<category><![CDATA[energy]]></category>
		<category><![CDATA[I. After]]></category>
		<category><![CDATA[mobile computing devices]]></category>
		<category><![CDATA[power]]></category>
		<category><![CDATA[solar tech]]></category>
		<category><![CDATA[W Mobile-]]></category>
		<category><![CDATA[W UMPC]]></category>

		<guid isPermaLink="false">http://solarcomputing.carrypad.com/2007/06/14/could-solar-energy-solve-the-umpc-battery-life-problem/</guid>
		<description><![CDATA[They are expensive and inefficient. Solar panels need to develop a lot before they can provide the average man on the street with enough energy to supplement a worthwhile portion of his energy intake. Mind you, the average man is pretty inefficient. Cars, lighting, heating, cooling. We sap up energy like there&#8217;s no need to [...]]]></description>
			<content:encoded><![CDATA[<p>They are expensive and inefficient. Solar panels need to develop a lot before they can provide the average man on the street with enough energy to supplement a worthwhile portion of his energy intake. Mind you, the average man is pretty inefficient. Cars, lighting, heating, cooling. We sap up energy like there&#8217;s no need to think about tomorrow. I&#8217;m sure the average person could cut their energy usage by 90% if they had the skills, time, money and resources to do it. At that point, solar power might be a more interesting proposition.</p>
<p><a href="http://www.solar-umpc.com/files/images/CouldSolarEnergysolvetheUMPCBatteryLifeP_97F0/image09.png"><img style="margin: 0px 5px 5px 0px" height="154" src="http://www.solar-umpc.com/files/images/CouldSolarEnergysolvetheUMPCBatteryLifeP_97F0/image0_thumb5.png" width="250" align="left"></a> Mobile computing is one of the areas that is already cutting its energy requirements buy huge amounts. Where notebook PCs can take 20-30W, ultra mobile PCs are taking 10W and in 2008 when we start to see dedicated ultra low power, ultra mobile computing devices, that power requirement is going to get slashed down to the sub 5W level. Intel is talking about sub 4W and VIA have just launched the <a href="http://www.ultramobilelife.com/index.php?option=com_content&amp;task=view&amp;id=309">3.5W Mobile-ITX board</a>. Of course, the reason for this is not because of energy conservation, its because of heat, size and weight. Mobile devices need to be small and light. Small devices can only dissipate a certain amount of heat and light devices can only contain a certain amount of battery. The last thing we want is a UMPC melting through the bottom of our bag!</p>
<p>One nice side-effect of all this drive for tiny, light devices is that solar energy starts to cash-in. Smaller energy requirements means smaller solar panels which means lower costs and higher mobility. Right now, today, if you took the best solar technology and made a fold-out sun-shade for a UMPC of about 20x20cm, you would be able to power the UMPC non-stop during sunshine. Its true. The best solar tech is <a href="http://www.energy.gov/news/4503.htm">reaching 40% efficiency</a> in the lab and at that rate a 20x20cm panel would provide up to 40W of power. Unfortunately, this is lab-tech at the moment and good quality, mass produced solar panels are down at the 15% efficiency level. Also add in the fact that many places don&#8217;t get much sun&nbsp;and you can see why its not really possible today. </p>
<p><a href="http://www.solar-umpc.com/files/images/CouldSolarEnergysolvetheUMPCBatteryLifeP_97F0/image04.png"><img style="margin: 0px 10px 5px 0px" height="180" src="http://www.solar-umpc.com/files/images/CouldSolarEnergysolvetheUMPCBatteryLifeP_97F0/image0_thumb2.png" width="147" align="left"></a> But lets take the <a href="http://www.rewarestore.com/product/020080001.html">Reware Juice Bag</a> as a good&nbsp;example of a useable bit of solar tech. It can provide up to 7W of power from a 20x30cm panel stitched into the backpack. That&#8217;s about 25W of stored energy per sunny day if you take into account losses on storage. Today, that would give you about 2-3 hours UMPC usage but with a 5W UMPC, you&#8217;re looking at&nbsp;5 hours usage. Drop down to 3W (2010 perhaps) and&nbsp;8 hours of battery life starts to get really useful. Lets assume that by 2010 the efficiency of Solar panels in increased by 50% and you&#8217;ve got full-day power from a panel that&#8217;s the size of a UMPC.</p>
<p>OK, its not 100% practical for everyone to be sitting outside looking for sun but it would work for a lot of people. And its just one example. How about&nbsp;taking the same calculation and scaling it up to a classroom full of UMPCs. You could power a full class of 30 with a few square meters of solar panel. Costs would be sub $1000 and if you compare it to 30 normal PC&#8217;s taking 150W per hour for 4 hours per day. (30 x 150 x 5 = 1.8KW) you are not only helping the environment but you&#8217;re reducing your air-con costs, noise&nbsp;and starting to get to the point where you save significant amounts of money. For a university that has 2000 PC&#8217;s deployed, well I don&#8217;t need to show the calculation do I. </p>
<p>After the solar-ump tour is finished I&#8217;m going to be following solar tech very closely on this blog and will continue to promote the marriage of&nbsp;ultra mobile PCs&nbsp;and solar tech. I don&#8217;t see the battery companies shifting towards more efficient battery technology so as solar energy starts to become a really interesting business opportunity we might start to see solar being integrated into specialist UMPCs for long-term outdoor usage. At some point in the future, when the calculations look attractive to the bean counters of this world, investment money will come pouring in to the mass market and the whole thing could take off in a very short time span. I predict, with excitement, &nbsp;that within 2 years we&#8217;re going to see solar accessories for UMPCs. Within 3 years we&#8217;ll see specialist UMPCs with integrated solar panels. I&#8217;m hoping that in ten years time, the extended battery will be a thing of the past.</p>
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		<title>Refining the Solar equipment. Li-Ion or Lead-Acid?</title>
		<link>http://solarumpc.com/2007/05/24/refining-the-solar-equipment-li-ion-or-lead-acid/</link>
		<comments>http://solarumpc.com/2007/05/24/refining-the-solar-equipment-li-ion-or-lead-acid/#comments</comments>
		<pubDate>Thu, 24 May 2007 12:54:00 +0000</pubDate>
		<dc:creator>Chippy</dc:creator>
				<category><![CDATA[Uncategorized]]></category>
		<category><![CDATA[aa batteries]]></category>
		<category><![CDATA[aa battery charger]]></category>
		<category><![CDATA[battery]]></category>
		<category><![CDATA[Li-Ion]]></category>
		<category><![CDATA[Li-On]]></category>
		<category><![CDATA[power]]></category>
		<category><![CDATA[samsung q1]]></category>

		<guid isPermaLink="false">http://solarcomputing.carrypad.com/2007/05/24/refining-the-solar-equipment-li-ion-or-lead-acid/</guid>
		<description><![CDATA[I&#8217;ve just had a nice conversation with my energy advisors, Select Solar, about some of the issues I&#8217;ve seen with the tests I&#8217;ve done so far.&#160; The main problem being that Li-Ion batteries will not trickle charge. They require a certain level of stable voltage/current before they start to charge and this wastes the possibility [...]]]></description>
			<content:encoded><![CDATA[<p>I&#8217;ve just had a nice conversation with my energy advisors, <a href="http://www.selectsolar.co.uk/index.php">Select Solar</a>, about some of the issues I&#8217;ve seen with the tests I&#8217;ve done so far.&nbsp; The main problem being that Li-Ion batteries will not trickle charge. They require a certain level of stable voltage/current before they start to charge and this wastes the possibility of charging a battery at lower sun power. In fact, on a hazy day or with light cloud cover, the sun power might not actually go above 70% and you have no chance to charge anything. This could be&nbsp; major problem and I&#8217;ve decided to try and address it. </p>
<p>A&nbsp;solution to this problem, <a href="http://www.solar-umpc.com/2007/05/solar-panel-testing-tough-calculations.html">as I mentioned before</a>,&nbsp;is lead-acid batteries. These are the type you will find in your car and are a tried, tested, reliable and relatively cheap solution. The problem is that they are also extremely heavy &#8211; at least 400% of the weight for like-for-like power storage. They also operate at 12v which means voltage conversions (and more electronics and power-wastage) in order to operate the UMPC.</p>
<p>The decision I&#8217;ve made is to buy a&nbsp;70W/hr 12v lead-acid battery (2200g) and to try and use this as a charge buffer. Here&#8217;s a little sketch of the planned set-up.</p>
<p><a href="http://www.solar-umpc.com/files/images/RefiningtheSolarequipmen.LiIonorLeadAcid_D1A1/solar18.jpg"><img height="238" src="http://www.solar-umpc.com/files/images/RefiningtheSolarequipmen.LiIonorLeadAcid_D1A1/solar1_thumb4.jpg" width="400"></a> </p>
<p>The idea would be that I connect devices to the lead-acid battery as the solar power increases during the day. For example, I might add a couple of AA batteries or my mobile phone in the morning. At mid morning I might replace it with the Li-On battery and during the peak hours I could re-attach the AA battery charger with 2 or 4 batteries depending on sun power. </p>
<p>Two problems I can see here:</p>
<ul>
<li>How do you know the charge on the lead-acid battery?</li>
<li>Will the lead-acid battery be able to feed up to 1.5 Amps?</li>
</ul>
<p>There&#8217;s only one way to find out. I&#8217;ve just put an order in for a 70W/hr lead acid battery and charge controller along with some fresh AA batteries, a powerbank tip adaptor for the Samsung Q1, a 12v charger for the mobile phone and something I&#8217;ve always wanted, a flexible USB LED-lamp!!!</p>
<p><a href="http://www.solar-umpc.com/files/images/RefiningtheSolarequipmen.LiIonorLeadAcid_D1A1/image03.png"><img style="margin: 0px 5px 5px 0px" height="238" src="http://www.solar-umpc.com/files/images/RefiningtheSolarequipmen.LiIonorLeadAcid_D1A1/image0_thumb1.png" width="176" align="left" border="0"></a> Later today I will probably be ordering the solar panel. I won&#8217;t be using the P3 Panel as the only advantage with that was that it could drive 19V into the PowerBank. Now that I&#8217;m going for a 12V source solution I&#8217;m going to be looking at the <a href="http://www.selectsolar.co.uk/pics/sunlinq.php">25W version of this Sunlinq panel</a> which is the same price as the 15W version of the P3 panel. There&#8217;s a risk that its going to be too big for the bike at 1m long but even if I fold 25% of it away, its still going to give more power than the 15W panel and during mid-day pause and work sessions I hope to get the full 25W out of it.</p>
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		<title>Daily power requirements.</title>
		<link>http://solarumpc.com/2007/05/18/daily-power-requirements/</link>
		<comments>http://solarumpc.com/2007/05/18/daily-power-requirements/#comments</comments>
		<pubDate>Fri, 18 May 2007 12:17:00 +0000</pubDate>
		<dc:creator>Chippy</dc:creator>
				<category><![CDATA[Uncategorized]]></category>
		<category><![CDATA[day]]></category>
		<category><![CDATA[nokia 6380]]></category>
		<category><![CDATA[PC. Well]]></category>
		<category><![CDATA[power]]></category>
		<category><![CDATA[target markets]]></category>
		<category><![CDATA[umpc]]></category>
		<category><![CDATA[W Emergency]]></category>
		<category><![CDATA[W Extended]]></category>
		<category><![CDATA[W Mobile-]]></category>
		<category><![CDATA[W Phone]]></category>
		<category><![CDATA[W Total]]></category>
		<category><![CDATA[W. In]]></category>
		<category><![CDATA[worst case scenario]]></category>

		<guid isPermaLink="false">http://solarcomputing.carrypad.com/2007/05/18/daily-power-requirements/</guid>
		<description><![CDATA[I&#8217;m quite lucky to have been able to test a lot of UMPCs out over the last year. Most have been good in their own target markets but only some have been good for me.&#160;One of my favorites, the Kohjinsha SA1, an AMD based device is also one of the most-power efficient too and I [...]]]></description>
			<content:encoded><![CDATA[<p>I&#8217;m quite lucky to have been able to test a lot of UMPCs out over the last year. Most have been good in their own target markets but only some have been good for me.&nbsp;One of my favorites, the Kohjinsha SA1, an AMD based device is also one of the most-power efficient too and I took it to CeBIT this year where I used it exclusively for 5 days. It worked well and it demonstrated to me how much I might use a PC in one day. During the daytimes I was able to get by with a single charge &#8211; 4 hours. In the evening I was using it for another 2 hours, minimum! OK. CeBIT was a worst-case scenario. There was breaking news all over the place and there was one point where I was walking to a meeting with Intel and trying to edit and post a news entry at the same time. I don&#8217;t expect to be doing that on the bike! I do expect to be stopping 2-3 times per day for 30-60 minutes at a time though. Primarily to update my location, photos and geotags and to make quick reports here and also to work on any news that&#8217;s breaking. In the evening I expect to do a small amount of video editing, uploading and maybe a longer post, chat, IM etc etc. 2 hours is what i&#8217;ll give myself in the evening depending on the forecast for the next day.</p>
<p>At 9W drain (hopefully less in evening with low backlight and careful control of HSDPA and WiFi) that&#8217;s about 36W per day.</p>
<p>In addition to the UMPC I will have:</p>
<p><strong>Mobile Phone</strong>. This is a Nokia 6380 with the 3.3v 900mah battery. 3watts. I will use this as my email and quick blog news checker using the gmail java app and the opera mini browser with bloglines mobile. These are combinations of applications that I&#8217;ve found very efficient and there&#8217;s really no need to turn on the UMPC to read email and RSS text. I can even do short emails on the phone too. If something interesting comes up then i&#8217;ll take the UMPC out of hibernate and do further reading, research or even email or blog. If I throw an hour or so of MP3 or FM radio in, I estimate that one charge per day on the 6280 will see me through.&nbsp;That will take about 5W of power from the power bank or I might be able to charge it in the early/late part of the day when the suns power falls below 70%.</p>
<p>Camera. This takes 4 x AA batteries. I use 2300mah 1.2v rechargeable batteries that should (if I use the camera carefully) last up to two days. That&#8217;s again, 5W per day. Charging will have to come from the solar panel during the day. Hopefully this can be done for an hour earlier or later in the day. Testing and research into different types of chargers needed. Smaller capacity batteries could also be useful.</p>
<p>GPS logger. This takes 2 x AA batteries every 15 hours. I hope that 2 batteries lasts me 2 days so that&#8217;s 2.5W per day. I will take a Bluetooth GPS device in case the logger fails. I think it lasts 10 hours on a 3W battery and can be charged from a USB port so its much the same in terms of power.</p>
<p>Lamp. This will be a very efficient LED lamp. Its possible to get ones that are solar powered or hand-cranked. I expect this to be a negligible drain. I will even take a few candles just in case. Bear in mind that it will be light until&nbsp;2200 and will get light again at 0500. I don&#8217;t expect to be awake much during these hours!</p>
<p>Finally, something I haven&#8217;t mentioned yet, a backup PC. Well its more of a web tablet really. Its the Nokia N800 and it will run for 3-5 hours on a 5W battery. That&#8217;s very efficient and could serve as an email tool, IM tool and, at a pinch, blogging tool (although i&#8217;ll have to look into a mini keyboard solution for it.) This will only be used if the worst happens. I.e. I run out of power or the main UMPC breaks. Otherwise I won&#8217;t use it and it will stay packed away. </p>
<p>Total daily usage:</p>
<p>UMPC: 36W</p>
<p>Mobile Phone: 5W</p>
<p>AA batteries for camera: 5W</p>
<p>AA batteries for GPS logger: 2.5W</p>
<p>Total daily power usage: 48.5W</p>
<p><a href="http://www.solar-umpc.com/2007/05/solar-panel-testing-tough-calculations.html">In the previous post</a> I estimated I could average 48W solar power collection and storage per day. Bingo! Now, did I forget anything? </p>
<p>The other luxury I will give myself is a fully charged set of batteries before I go. I don&#8217;t think its unreasonable as anyone in their right mind would ensure that their batteries were charged before they went. Here&#8217;s the battery power that I will take with me:</p>
<ul>
<li>Powerbank: 56W
<li>Extended battery: 60W
<li>2nd extended battery. Empty&nbsp;
<li>8xAA batteries for rotating through camera. 20W
<li>4xAA batteries for rotating through GPS. 10W
<li>Phone charged. 3.5W
<li>Emergency UMPC charged. 5W</li>
</ul>
<p>Total starting power: about 150W.</p>
<p>In theory, that lot will give me a&nbsp;1 day buffer which means at some point in the tour, I can have a day of bad weather and continue as normal.</p>
<p>I will talk to select solar next week to see what they think of my estimates and if they give it the thumbs-up Ill start real testing &#8211; assuming the sun comes out!</p>
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		<title>Solar panel testing. Tough calculations.</title>
		<link>http://solarumpc.com/2007/05/15/solar-panel-testing-tough-calculations/</link>
		<comments>http://solarumpc.com/2007/05/15/solar-panel-testing-tough-calculations/#comments</comments>
		<pubDate>Tue, 15 May 2007 15:04:00 +0000</pubDate>
		<dc:creator>Chippy</dc:creator>
				<category><![CDATA[Uncategorized]]></category>
		<category><![CDATA[Bonn]]></category>
		<category><![CDATA[bonn germany]]></category>
		<category><![CDATA[day]]></category>
		<category><![CDATA[Germany]]></category>
		<category><![CDATA[nbsp]]></category>
		<category><![CDATA[power]]></category>
		<category><![CDATA[trickle charge]]></category>
		<category><![CDATA[V. That]]></category>
		<category><![CDATA[voltage conversion]]></category>
		<category><![CDATA[W This]]></category>

		<guid isPermaLink="false">http://solarcomputing.carrypad.com/2007/05/15/solar-panel-testing-tough-calculations/</guid>
		<description><![CDATA[The weather is still bad here in Germany and there&#8217;s no chance of getting reasonable testing done on a solar panel at the moment. The forecast is also bad so I&#8217;ve decided to send the test P3 panel back. In the very short time I was able to test it I was able to learn [...]]]></description>
			<content:encoded><![CDATA[<p>The weather is still bad here in Germany and there&#8217;s no chance of getting reasonable testing done on a solar panel at the moment. The forecast is also bad so I&#8217;ve decided to send the test P3 panel back. In the very short time I was able to test it I was able to learn a lot though and its given me some thoughts about how I will move forward. This post goes over some of the stats, figures and calculations so its not exactly the most interesting post for the average reader. For those that are thinking about doing a similar thing though, this could be a very interesting post for you!</p>
<p><img style="margin: 0px 5px 5px 0px" src="http://www.umpcportal.com/gallery/d/4042-2/IMG_3073.JPG" align="left"> A very important lesson was learnt on the first day&nbsp;- the&nbsp;charging system doesn&#8217;t even start working until the sun reaches 70% of full power. This is due to the Li-ion charging system on the powerbank. It wont trickle charge so only kicks into life when there&#8217;s enough power to drive it. This renders about 8 hours sunlight per day as unuseable with this set-up.</p>
<p>The second thing learnt is that the charging system doesn&#8217;t&nbsp;work faster if there&#8217;s more power available. It seems that the power bank needs 12W to charge and will not take any more power if, say, 15W is available.&nbsp; Thinking back to my basic electronics, I guess this makes sense! This means more waste though and requires balancing the charging requirements with the power available if i&#8217;m to use this set-up.</p>
<p>One very nice feature of the P3 panel was that it was able to charge the TabletKiosk powerbank directly, without voltage conversion. That helps a lot because the other solar panels i&#8217;ve looked at only drive 12V. That would mean converting voltage up to 19V and losing power in the process. Taking a few of the figures learnt, there&#8217;s a simple equation gives me the theoretical power possible per day.</p>
<p><strong>Power available (W/hr per day) = Powerhrs x&nbsp;ChR</strong></p>
<p><strong>Powerhrs</strong> is the number of hours per day when the sun is over 70% power. (taken from sun power records. June. Bonn, Germany) This is about 7 hours in May, June and July.</p>
<p><strong>ChR</strong>&nbsp;is the charge rate of the power-bank (must be about 0.7 of solar panel rating for best efficiency.) = 12W</p>
<p>This assumes a sunny day. No cloud cover. No shadows and the panel facing the sun.&nbsp;The changes of that happening are slim. I have the advantage that I&#8217;ll only leave the house if the 6-day forecast is good so I can reduce this risk to a minimal amount but I think I&#8217;ll lose another 20% through shadows and positioning while I&#8217;m moving. If cycling around becomes a problem with shadows and sun positioning I might have to carefuly plan my stops in order to maximise solar panel positioning. Maybe a stop at 10-11 and again at 3-4 would help get the best out of the early and late light.</p>
<p>So lets plug&nbsp;the figures&nbsp;into the equation and see what we get with the P3 solar panel and the TabletKiosk MP3400 power bank.</p>
<p>7&nbsp; x 12 = <strong>84W/hr energy per day</strong> assuming 15W from panel at max sun power.</p>
<p>Now for the second part of the equation:</p>
<ol>
<li>There&#8217;s no such thing as a perfectly sunny day. Especially when you&#8217;re cycling. I&#8217;ve been advised to use a figure of 4 hours per day for sun. In my tests, on&nbsp;two sunny&nbsp;periods, I managed to load a 56W/hr battery in about&nbsp;8 hours so the equation seems to be roughly OK. At a 12W load rate, that&#8217;s about 4 full hours of&nbsp;sun so&nbsp;I agree with the 4 hours rule. &nbsp;
<li>You can not charge and use the bank at the same time. This means that a second power source is needed for the daytime. In the evening its fine because I run from the powerbank. I could use the battery on the device UMPC in the daytime of course but what happens when its empty?&nbsp;Can I charge it from the solar panel (that&#8217;s stupid because I would need a second UMPC just to charge the battery &#8211; the solar panel will not be able to run AND&nbsp;charge a UMPC. Also,&nbsp;if there&#8217;s not enough voltage or current protection on the UMPC I would risk killing the UMPC) There&#8217;s is the possibility of&nbsp;topping up the UMPC overnight from the power-bank but&nbsp;If I do that, I have to consider the following&#8230;
<li>To charge other devices from the bank, there is something like 20% power loss through the charging circuitry.</li>
</ol>
<p>There&#8217;s one other point too. The powerbank can only store 56W/hr of power. Taking point&nbsp;1) &nbsp;into account brings me down to 48W/hrs on a sunny day which I guess solves the problem of limited powerbank capacity!</p>
<p>I think the best solution for point&nbsp;2) is to use a second power bank. This also has the advantage of giving me a spare powerbank should one fail, and, being able to fill a second device should I find myself with sun and nothing to charge! It also reduces the risk of killing the UMPC and avoids the wastage of 3)</p>
<p>So we&#8217;re now at 48W/hrs per day. Its incredibly poor considering the power of the sun. In theory, the suns power is equivalent to 1Kw of energy for every m2 and that makes solar energy capture and storage&nbsp;horribly horribly inefficient. Consider that in&nbsp;4 hours, about 2KW/hr of energy will be hitting the&nbsp;solar cells on the&nbsp;panel&nbsp;I tested.&nbsp;Yes 2000W/hrs. Enough energy to power a small UMPC for&nbsp;1 month&nbsp;at 8 hours per day!&nbsp;The efficiency is a crazy 48/2000. Just over&nbsp;2%. </p>
<p>How can this be improved?&nbsp;One thing I could do is to find a lower-power charging solution. That is, start storing energy before the sun reaches 70%. If you can start storing energy when the sun is at 50%, you have a few more hours per day and if you can start gathering energy at 30% power, you can even get some when its cloudy!</p>
<p>The second variable is the power-loss on charging. This is generally because the Li-ion batteries need a fairly strict charging voltage and current and there&#8217;s a fair bit of circuitry there to protect them. Lead-acid batteries could be better but, wow, the weight! To store just 70W/hr of energy you&#8217;re looking at 2.5KG. The 56W Li-Ion power-bank I have is just 500grams.&nbsp; </p>
<p>The third option is to get a panel with more efficient solar cells.</p>
<p>Having said all that though, this is an off-the-shelf system that appears to work. I didn&#8217;t need to make any modifications at all and I like the idea that this project could go ahead with off-the-shelf equipment. It makes it easier for others to replicate it. </p>
<p>The big question now is, <strong>will 48W per sunny day be enough?</strong> If so, I don&#8217;t have to worry about the terrible efficiency and high cost. It will be enough to provide me with power where I can&#8217;t get it. I&#8217;ll be analyzing the power requirements in the next post to see if 48W&nbsp;per sunny day is enough. If it isn&#8217;t, i&#8217;ll have to go back and look at other options.</p>
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		<title>Choosing the Solar UMPC</title>
		<link>http://solarumpc.com/2007/05/11/choosing-the-solar-umpc/</link>
		<comments>http://solarumpc.com/2007/05/11/choosing-the-solar-umpc/#comments</comments>
		<pubDate>Fri, 11 May 2007 09:09:00 +0000</pubDate>
		<dc:creator>Chippy</dc:creator>
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		<category><![CDATA[UMPCs]]></category>

		<guid isPermaLink="false">http://solarcomputing.carrypad.com/2007/05/11/choosing-the-solar-umpc/</guid>
		<description><![CDATA[Its decision time on the UMPC and I think I&#8217;ve just about come to my conclusion &#8211; The Samsung Q1b HSDPA. Its not perfect but it covers the important requirement of efficiency very well. Maybe in a few more months there will be better options but right now I need to focus on one device [...]]]></description>
			<content:encoded><![CDATA[<p><a href="http://www.solar-umpc.com/files/images/ChoosingtheSolarUMPC_14D24/image02.png"><img style="margin: 0px 0px 5px 5px" height="240" src="http://www.solar-umpc.com/files/images/ChoosingtheSolarUMPC_14D24/image0_thumb.png" width="180" align="right" border="0"></a> Its decision time on the UMPC and I think I&#8217;ve just about come to my conclusion &#8211; The Samsung Q1b HSDPA. Its not perfect but it covers the important requirement of efficiency very well. Maybe in a few more months there will be better options but right now I need to focus on one device and start testing and getting used to it. </p>
<p>Let me take you through the reasoning though. You might be thinking about the same thing yourself so&nbsp;I&#8217;ll list my requirements and then go through the options.</p>
<p>Requirements.</p>
<ul>
<li>Power efficient. Obviously. I&#8217;m looking for sub 10W average power drain for a total power budget of under 60W per day. (More on the power-budget in another post.)
<li>Lightweight. All UMPCs are lightweight. This shouldn&#8217;t be a problem.
<li>Bright screen. Some are better than others and when you&#8217;re outside, this can make a huge difference. Put it this way, I&#8217;d rather be sitting on the terrace of a cafe rather than inside on my own!
<li>Keyboard. I&#8217;m going to be doing a lot of typing so this is going to be an important requirement. Nearly all built-in keyboards are nothing more than thumbboards. I will have to consider external keyboards
<li>Protective case. A slip case isn&#8217;t going to be enough. I need a very good protective case. Preferably rugged.
<li>Ruggedness. 8 days on the road is going to be tough on a UMPC. I&#8217;m concerned about dust and the hard drive.
<li>Bluetooth connectivity (for data through mobile phone). There are other connectivity options including connecting a mobile phone via USB and getting a UMPC with built in 3G data modem.
<li>SD card slot for digital camera images.
<li>Extended battery. Generally the batteries with UMPCs are around 20-30W/hr types. an extended battery is going to make charging easier.
<li>Reliable. A proven track record is important.
<li>Cost effective. Upper limit is around 1500 Euro for all UMPC equipment.</li>
</ul>
<p>I have already chosen VIA as the platform I will use. Intel is powerful but can start to sap power very quickly is not used carefully. One stray process and you can eat 15W in an hour. I don&#8217;t want that to happen. AMD is another option and there are some nice low power solutions around. The only problem is that the processing power of the AMD solutions is limited. I have edited a couple of movies on an AMD platform and it was a long process. I can not afford to leave the PC for one hour crunching videos and sapping energy.
</p>
<p>VIA have been on the UMPC scene since the Origami launch in March 2006 and the core of their solution is the C7-M ULV CPU. Its available in 1, 1.2 and 1.5Ghz versions but until recently, only the 1Ghz versions have appeared in UMPCs. Amtek (OEM), Samsung and Uren are really the only manufacturers that already have VIA-based UMPCs on the market and although there are three more available this month, they are new, untested and not available for immediate delivery. </p>
<p><a href="http://www.umpcportal.com/products/product.php?id=13"><img style="margin: 0px 10px 0px 0px" src="http://www.carrypad.com/images/t700-small.jpg" width="75" align="left"></a>The T700 was the first VIA-based UMPC. Its a basic device compared to some of the UMPCs we&#8217;re seeing today with a simple style, no SD and no&nbsp;web cam.&nbsp;It has proven to be a solid device though. It has an extended battery and there are bump cases available for it. Its also good value. You can pick up&nbsp; branded versions for under $800. The big problem with the Amtek T700 though is its average battery life. 11-12W drain is normal. It is also lacking the SD card slot required. </p>
<p><a href="http://www.umpcportal.com/products/product.php?id=39"><img style="margin: 0px 10px 0px 0px" src="http://www.carrypad.com/images/SamsungQ1-small.jpeg" width="75" align="left"></a>The second option is the Q1b from Samsung. This is the VIA version of the Q1, another UMPCs released as part of the Origami project from Microsoft. Its a slightly more attractive design and comes with a 280nits screen. Brighter than the T700. Again there&#8217;s no mouse and no SD card slot but bump cases and even a specially made Samsung organiser pack with keyboard is available. In fact, I&#8217;m using one&nbsp; to type this right now and its a very very nice keyboard. The other major advantage of the Q1b is its battery life. It can average well below 10W and is even reported to run in a battery saving mode with low-backlight for 4 hours. That&#8217;s about 8W average drain. Again, its a good value buy although its not available in its basic form in Europe because Samsung introduced it here in Germany with a built in HSDPA modem, bigger disk and more memory. Potentially a great advantage but the price is quite a bit more than the T700 is available for. It would stretch the budget when taking into consideration the keyboard and protective cover.</p>
<p><a href="http://www.umpcportal.com/products/product.php?id=41" target="moreinfo"><img style="margin: 0px 10px 0px 0px" src="http://www.carrypad.com/images/uren-v1_icon.jpg" width="75" align="left"></a>Finally, there&#8217;s the Uren V1. Unfortunately this one is very quickly out of the running because it&#8217;s not available at outside Asia. Its also a car-focused UMPC. The most difficult thing about the Uren though, is that no-one has really written any reports about it in English. Its certainly not a UMPC that I&#8217;ve been able to get hold of and test so at this stage it goes straight to the bottom of the list.</p>
<p>So there you have three UMPCs. One looks like good value and capable. The other looks like its perfect for the job but expensive and the other is out-of-reach. I mentioned a budget of 1500 Euro for the UMPC. This includes the cost of protective cover, keyboard and extended battery. When I add up the costs of the Q1B HSDPA, the organiser pack (with the wonderful keyboard) and an extended battery I come to just under 1500 Euro. Phew! I&#8217;ve even got some spare change for a USB-SD adaptor. The Q1B HSDPA it is then and as you might have seen on UMPCportal.com, <a href="http://www.umpcportal.com/modules/news/article.php?storyid=563">I have already taken delivery of one</a>. Unfortunately it had a faulty USB port so its gone back&nbsp;but the short time I spent with it was really nice. The HSDPA modem is going to be a great advantage and I&#8217;ve already transferred the data portion of my Vodafone tariff to a new SIM card. No messing with Bluetooth or cables and no worrying about keeping the mobile phone charged. If the phone dies there&#8217;s always skype!</p>
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