Solar power

[falk]

Hey all, in light of this year's theme, I'd love to give solar power a try. Are there books, web sites, other resources that people can recommend?

I went to the Solar expo in San Jose the other day. Most of what I learned is that the vendors of solar panels aren't interested in selling to hobbiests. (They practically threw me out when they found out I wasn't a licensed contractor.)

A few resources I found:

http://www.sunpowercorp.com/ (they just broke the 20% barrier)
http://www.nanosolar.com/ (thin-film technology, not available yet)
http://www.solarelectricsupply.com/Char ... index.html (controllers)
http://www.optimabatteries.com/publish/ ... cycle.html (deep-cycle batteries)
http://www.cafeelectric.com/ (motor controllers for vehicles)
http://evcl.com/ (Hobby EV notes & pictures)

[Fex]

I found this groovy kit online... if you're not an engineering type, these kits sound like a great investment. Portable power station with a panel, battery, inverter, 12vDC and 115vAC outlets 'n all dat stuph... you can also charge it up from an outside power source like a genny or a car powerpoint if there's no sun, and you can add extra panels and storage batteries.

might be worth looking into. I'd really like to try the solar approach too, but I'm not much of a techie where electronics are concerned and would probably trust an off-the-shelf system over something I try to rig myself.



[url]http://www.solar4power.com/solar-power-devices.html[/url]

[phil]

Take a look at
http://www.cieux.com/bm/bmtoc.html#perennialGuides
where I have links to sites about electricity for long term camp outs, the Alternative Energy Zone, and so on. Each site I link to has further links, spreading the web, so to speak.

On a practical level, getting _useable_ electricity from a solar panel is an expensive proposition. It can be a considerable investment, so if you can get stuff you use year round, it makes the cost more bearable.

_Generally_, you're better off if you can use solar panels and batteries to power 12VDC gear instead of using an inverter. However, this adds to the cost.

Good luck and have fun.

[Bob]

Anybody looking forward to acoustic raves this year?

[diane o'thirst]

If you're not a tech-head, you have multiple resources for just buying standalone solar lights.

I just picked up a string of solar-powered LED lights at Sportsman's Guide for $1/foot. Last year I got three solar spotlights from Dr. Leonard's and they made my "Definitely bring back next year and GET MORE" post-Playa list. Single solar spotlights work pretty good for bike headlights, too: they run about $15. Just park your bike in the sun during the day and you'll have 8 hours of illumination that night.

[robotland]

Single solar spotlights work pretty good for bike headlights, too: they run about $15. Just park your bike in the sun during the day and you'll have 8 hours of illumination that night.

Great Idea, that!

If you're okay with amber lighting, you can find more and more clearanced solar pathway lights as the new brighter white LEDs take over. Often buying a set of these brings the individual cost down to a buck or two per unit! It helps to pre-charge the NiCad batteries before leaving for the playa, and to NOT install them until you've set up camp since they'll think "I'm in a box with camp junk in the car!" is the same as "it's nighttime!" and run their cells down. My pal Sparkzy has cleverly modified solar lights by trading out the amber LEDs for UV or blinking red ones, to good effect. Or you can gut the mechanisms and install on your bike or camp!
Another resource- Check your local newsstand for Home Power magazine.

[diane o'thirst]

I always pack my solar lights in the roofrack, where they'll charge all day while I'm driving down.

The other nice thing about the solar spotlights is that they unplug from the charging plate. Then you can charge the plate in the sun and pack the lights in a box.

[The CO]

I charge the lights beforehand and then slip a small piece of cellophane tape over the ends of the battery before packing them. That way, they are charged & ready when they get to the playa. Also, pack them on the TOP of a box thats last in/first out, so you have some kind of light when you get there.

[Zhust]

Hey all, in light of this year's theme, I'd love to give solar power a try. Are there books, web sites, other resources that people can recommend?

Alternative Energy Zone has a wiki with helpful information on electricity and other alternative-energy topics.

I guess a few things I've learned about solar:

• The watt ratings are always for peak sunlight and are sometimes exaggerated, especially with cheaper products. A rough estimate for a solar panel on a sunny day on the playa would be about 5 hours * the watt rating, giving you energy in watt-hours. If the panel is pointed straight at the noon-day sun, you might see 90% of rated power, and by the time the sun is at 4-fingers [4-fingers-width above the mountains] it's only less than 5% of its rated power. Even a light layer of dust you can write your name in might reduce the output by 20% or more.
• Panels are rated for "open voltage" and "short-circuit current." Multiplying these values together is not the wattage of the panel. Since solar cells have a fairly high output-impedance, the larger the load (the more current) the lower the voltage goes. A panel to charge 12-volt batteries might have an open voltage as high as 20 volts or more, but once connected to a battery to charge, the voltage will settle down to the battery's voltage although the panel will be supplying charging current at that voltage.
• If you're picking a panel to charge a battery, select the panel so it delivers around a full charge in a day (batteries should typically be charged over 10 hours time, and there's about 13 hours of sunlight at Burning Man in August). That is, if you have a 7 amp-hour, 12-volt sealed lead-acid battery, that's 84 watt-hours, so given 5 useful hours of total sunlight (see the point above), you should be looking for around a 84 watt-hours / 5 hours = 17 watt panel.
• Another example: a medium-sized "Group 31" car battery has a capacity of around 100 amp-hours, so at 12 volts, that's 1,200 watt-hours. A panel to charge the battery in a day would need to be about 240 watts. Using the small 17-watt panel above would mean the battery would take about 14 days to charge fully. Note also that a lead-acid battery will self-discharge at a rate of about 2%-5% per week -- that's about 5 watt-hours per day on this size battery, so (remembering that 5-hour usable light) it's like your panel is 1-watt smaller than rated.
• Check out those suppliers you mentioned and get an idea for the cost-per-watt of a quality panel. It should scale pretty linear to smaller panels. Getting a good deal is best -- 10% less than that price, for instance. Getting a great deal isn't -- 50% less than the going price-per-watt more likely means you're getting a panel that really provides only 50% of its rated power.
• "Amorphous silicon" panels are lower quality than "crystalline silicon" panels.

[timburly]

I noticed you where thinking about using optima deep cycle batts...those are not good for a solar application.....they are cheap and will only last you a year or two...Find a battery that is made for solar applications, this will run you more $$$ of course but if maintained properly can last you a decade or more. Also look around for kits, many solar suppliers have a "weekend cabin" type kit these include a solar pannel or two charger interconnects and the proper batteries. I've seen them in the 800 range on up depending on the output your looking for. Another thing to consider is wind power. I think we will be going with a combo of Wind and Solar this year in our camp. Allthough the playa is unpredictable and we may not see any wind what so ever on '07.

[unjonharley]

I would not have a battry that takes 13 hours to charge.. I want to use them.. Not spend all day sucking money..I'm thinking of going with car batteries..One on the charge and one workng..I can use the solor panels as a shade for my ride..Fuck, YOu guy are working your brain to death.

[motskyroonmatick]

I agree with timburly---Optima bateries are a bad investment. I had one in a bone stock for ranger and it lasted me 2 years. The origional factory battery lasted 8 years. I will be purchasing the big lead acid deep cycle from costco. It has twice as much holding capacity as an optima.

I use solar @ burningman to power EL wire on my mailbox and bike. I also run my Mr. Polando and El Subcomandante Marcos evaporator, camp music devices and shelter fans off of 12 volt solar.

I Bring an incerdibly loud 10,000 wat generator to power my welder and 110 tools. I only run it when I am fixing something.

[MikeVDS]

Optima bateries are a bad investment. I had one in a bone stock for ranger and it lasted me 2 years. The origional factory battery lasted 8 years. I will be purchasing the big lead acid deep cycle from costco. It has twice as much holding capacity as an optima.

From your perspective, they are a bad investment, but they are some of the best at their price for other applications. For lead acid they are some the best energy density/weight you can find that are not specialty($$$). Also they hold a pretty steady and square voltage curve. So it really depends on the application. If you can take all the weight in the world, then the big cheap ones are great, but if weight becomes a factor you have to look at other things.

I'm not trying to talk you into optimas, since the weight is not a factor for BM, but I worked with many different batteries when I was working on solar powered boats and did a lot of testing, and for that type of application, they can be the best for the price. So the people who recommend them, are correct that they are good batteries, but may not know some of the finer points of batteries or how you'll be using them.

[motskyroonmatick]

MikeVDS,
You are right that application is everything. My main disapointment with the optima is the life of the battery in a time based sense. Purely dollars spent vs. years of life.

[timburly]

What about disposal of those batts that only last a few seasons at the most......creates havoc...

I'm coming from an off the grid perspective. Batteries are a large portion of investment and it seems silly to me to keep shelling out 150 bucks per battery every two years, at the most, for somthing that is sub-par.

Bottom line is proper maint. Optima doesn't require any as far as I know...well other than cleaning the terminals from time to time. But don't store them dead. Always have a trickle charger on them throughout their storage life among other things. Check out the net there is plenty of resources about batteries.

Go talk to a local solar dealership, one that installs large PV systems not some autoparts store that sells a 15watt panel for the RV.

[gyre]

There are used high grade panels sold as they are changed out.
It is not worth using solar anything just for burning man unless you get it on closeout.
Max out your efficiency in the devices you use.
You can get good rechargeable batteries.
Don't get suckered on the D cells.
The real ones cost you money.
The ones at walmart are AAs in a D package.
Even the best AA and AAAs are reasonable.
I use alkaline duracells.
I used one or two sets of AAAs in a 3 watt headlamp in two weeks.
Everready leaks.

If you own an rv you can justify getting a good solar setup for that, if you will be using it other times.

My experience with Optima has been great.
An extremely low internal resistance that charges rapidly.
Mine is a standard, not deep cycle.
It has survived a race environment with no padding and a solid suspension.
The next dual battery setup I do will be two marine deep cycle Optimas, cranking and backup, a matched set from the same lot.
I have had no luck with deep cycle standard batteries.
I have had great luck with a semi battery as a home power supply on a float. (Exide Industrial)
It has never been deep discharged, but it has been abused.
I have a forklift battery too, but it is heavy.
Optima is an encapsulated wet cell battery.
The deep cycle is almost identical to the standard except higher weight.
Cranking is almost as good as the standard.

For lighting, 12 volt fluorescent is hard to beat.
If you want to push it, get low pressure sodium in 12 volts or use an inverter. (pure amber light)
LEDs cannot compete with fluorescent.
I recommend high K bulbs, whiter.

[Rusted Iron]

Has anyone encountered any problems with alkaline dust and solar panels?

I bought a couple of 5 watt units--less chargers than slow-down-dischargers. I'm using them to maintain the charges on the Rat car's marine battery and the one in the camper. I figured I'd leave the panels home during BM, and use the generator to recharge them, after I read that they shouldn't be exposed dust or alkalinity.

[unjonharley]

Has anyone encountered any problems with alkaline dust and solar panels?

I bought a couple of 5 watt units--less chargers than slow-down-dischargers. I'm using them to maintain the charges on the Rat car's marine battery and the one in the camper. I figured I'd leave the panels home during BM, and use the generator to recharge them, after I read that they shouldn't be exposed dust or alkalinity.

\/
I had a couple small panel in 06 they seem ok..This year I will have some small panel also thre panels for 35 watt charging power.

[AntiM]

Ours have held up pretty well. Plus we leave our poor little garden solars out all winter in the snow and they're still working.

[gyre]

It's worth checking with the manufacturer.
The dust has destroyed my shoes.

You might be able to seal the edges to protect the wafer.

[diane o'thirst]

My local Big Lots! has adjustable solar spotlights for $8.50. I'm going over there tomorrow (it's too late tonight) and pick up a few for my bike.

[DustMonkey]

I'm not sure how new this is, but I just stumbled upon it:

The Sunsei Solar Charger
http://www.solarcharger.com/s.nl/it.A/i ... ategory=62

This is a solar panel charger with all the gizmo's you need to just plug it directly into a deep cycle battery. This would be a great (and green) solution for those that can't (or don't want to) build a device themselves.

I haven't field tested, so I have no idea how well this works.

[timburly]

This year we're golden, we have a southwest windpower Air-X wind geny and about 200 watts worth of solar. For batteries we're using Trojan t-105's. All lighting with the exception of 2 compact florescents are LED's.

[falk]

I'm no longer convinced that Solar is appropriate for Burning Man -- the energy and pollution involved in building solar cells will never be paid back if you only use them a week or two during the year. (Unless, for instance, you install them on the roof of your house once you get back home.)

Now I'm contemplating wind power, which could theoretically be accomplished with surplus motors.

[timburly]

Wind geny's are relativly easy to build. Including alternator and tower..

http://otherpower.com/

[phil]

I'm no longer convinced that Solar is appropriate for Burning Man -- the energy and pollution involved in building solar cells will never be paid back if you only use them a week or two during the year. (Unless, for instance, you install them on the roof of your house once you get back home.)

That's the problem with much of what people buy for the event. Louise and I are lucky that a lot of our gear does triple or quadruple duty. We have three camping trips a year other then Burning Man, so we get to use our stuff more than just the Burn. We live in the San Francisco Bay Area, so a lot of our stuff is stored outdoors in anticipation of the big earthquake which will render our house uninhabitable for months (is New Orleans fixed yet? Years, maybe). And we are ham radio operators, and we participate in communications for a _lot_ of local events where we need shelter and long-term batteries (and these events are run as if they were disasters, so all us hams stay in practice for when the big one comes).

Now I'm contemplating wind power, which could theoretically be accomplished with surplus motors.

Similar issues apply. I agree that building solar panels is _much_ dirtier, and I know of no place that recycles them, but they're quiet and don't fall over and damage nearby vehicles, structures, and bodies. Most wind generators do their best work when the wind is too strong for any reasonable person to be out in it - fortunately, reasonable persons don't go to Burning Man. :-> But wind generators remain surprisingly noisy, and windy though it may be at Burning Man, it's more likely to be sunny than windy. I'm not sure which device would generate more electricity over the week.

And the issue of use after the burn remains. We can put a solar power in our window and keep our batteries trickle charged. In our development, we cannot put up a windmill. We can't put solar panels on our roof, either. But we can take our panel to events to help keep the battery charging during the event. We generally are in a parking lot or an office lawn with an in-ground sprinkler system, so stakes are prohibited. It's hard enough stabliizing an antenna mast, but less a windmill.

C'est la vie.

[BAS]

Wind geny's are relativly easy to build. Including alternator and tower..

http://otherpower.com/

Oh, sure! I was just thinking about going to bed, and have to toss a web site like that at me!!!


B.

[robotland]

MAKE magazine had a good article about building wind gennies as well. Perhaps two issues back...I'll go check and report.

[stew]

Anybody looking forward to acoustic raves this year?

I so hope we're going to see that. I've seen 'electronic' music genres (Drum 'n Bass, House) plaid by bands and it was beautiful. Just listen to The Bad Plus playing Aphex Twin!

[BAS]

MAKE magazine had a good article about building wind gennies as well. Perhaps two issues back...I'll go check and report.

Oh yeah! I got that issue, and the wind generator is what got me to subscribe. (Unfortunately, the magazine is packed in a box somewhere right now....)

What keeps the wires from getting too twisted around on one of those? I'd think that they would run the risk of twisting off if the wind chages direction too often. Or doesn't that happen?


Thanks!


B.