Batteries vs. Generators

[phil]

http://www.treehugger.com/files/2010/07/ask-pablo-generator-or-battery.php

I don't know who Pablo is, but he's at TreeHugger.com, and he thinks batteries win over gas or diesel powered generators, despite a higher initial cost.

Here's the summary: you have limited amounts of gasoline. If you calculate your needs for gas in terms of kWh (you're actually using the generator to generate electricity, remember) and buy batteries in that amount, it's cheaper in the long run and doesn't eat up nonrenewable oil, spew exhaust into the atmosphere, and the power generated by generators is not reliable because of surges, and it may not be useable alternating current for some devices.

Batteries are charged at home (or on the playa with sun or wind) using cheaply available electricity (probably generated by burning coal, but that's actually more efficient than buying gas and burning it in a gennie), and the batteries are reuseable for years. When they fail, the lead and sulfuric acid are recycled. Lead-acid batteries do not contain cadmium, lithium, and other high-cost precious metals.

The lead and sulfuric acid do not escape into the environment, assuming we're all responsible and recycle the batteries. Like British Petroleum, we can't capture our generator exhausts and contain the carbon dioxide, carbon monoxide, and the like. It all goes right into the air, no matter how responsible we are about pollution.

[Homiesinheaven]

sounds good to me! if your power needs are basic it seems like you get more power for less cost using batteries especially when you find good bulk deals on them online.

[Token]

This is great if you live in a 3rd world country ghetto and have utility power 16 or 18 hours per day.

If you are completely off grid, like the Playa, the investment and maintenence of solar or wind infrastructure would raise the cost orders of magnitude.

Nice try Phil, but for the 10 days per year playa usage, the small Honda inverters are both economically and environmentally more sound. (pun intended).

[some seeing eye]

The energy density of gasoline is 50 million Joules per Kg. Lead acid batteries can store about 150 thousand Joules per Kg. That's about a 300x difference by weight.

[Trishntek]

double post, sorry

[Trishntek]

The energy density of gasoline is 50 million Joules per Kg. Lead acid batteries can store about 150 thousand Joules per Kg. That's about a 300x difference by weight.

You cannot make that comparison without taking into account the energy source which provides the battery something to store. Of course, that would make it even worse.

I'll have a couple deep cells for lights and possibly music, but that's about it. Otherwise, the genset with overload protection will be our main source. Besides, our camp will have several electrical gadgets being played with at any given time.

[much2naughty2]

Both have their value and place. You must make a case by case analysis, of each installation, before you can state for certainty which is best. I've installed solar/battery systems in wilderness and other remote areas since 1976. There was no more cost effective solution. At the same time, where appropriate, we installed diesel and gas gensets. We even installed a 50 kw micro hydro generator, that replace diesel gensets.

You can't blindly say battery is the only solution with any credibility. Lead acid batteries are likely the worst recommendation for a battery choice. That already make your guy suspect Phil, of course anything from a site call treehugger.com might have a bias and an agenda.

If you can get more than 3 years out of a lead acid battery, using and storing it as you would for BM, you're doing great. On the other hand, I'ld be surprised if you couldn't get decades of use out of a honda getset.

All that said, I'll be installing my new solar panel on my RV and a second battery, as well as using a 3.5 KW genset. Cost analysis be damn, I just want it, so I bought it.

[Captain Goddammit]

What a load of absolute bullshit! "the power generated by generators is not reliable because of surges, and it may not be useable alternating current for some devices." ??? More often than not, the reverse is true! The quality of AC power supplied by batteries and the power generated (well, stored and released) by batteries is a function of the quality of the inverter used, NOT the fact that the energy came from a genny or a battery. Most affordable inverters make the shittiest AC power ever, usually square-wave.
Now factor in transporting enough batteries to get anywhere near the output a generator can produce. Hey Phil, can you sustain a 2 or 3 thousand watt-hour load on batteries, successfully, all day every day for a week? Nope... you can't... because you can't haul enough batteries to do it.

The simple fact is that the batteries available as of yet cannot store enough power to compete with gas or diesel generators.

If your total electric draw is down in flashlight-battery range, OK fine.

The money argument is bullshit, go and calculate how many batteries you'd need to equal what a $900 generator will do.

[much2naughty2]

The money argument is bullshit, go and calculate how many batteries you'd need to equal what a $900 generator will do.

The battery cost is less than half the equation Captain. I don't care if it's solar or wind generators, you still need to be able to charge the batteries on site. I got a great deal on a 110 watt solar panel for $225, but to charge batteries to supply a 2 kva load, I would need 20 or more panels, if I had sun 24 hours a day. Let's see, that's $4,000 worth of solar panels, another $1,000 for mounting hardware and frame, and $2,000 (low estimate) worth of batteries, and of course a good 2kva inverter will run $500 to $1,000, all to replace a $900 genset, that's of course if it's not cloudy... and the sun shines 24 hours a day.

Hum, Battery/Solar system (not counting transportation costs. $7,500

$900 generator(10 year life cycle x 10 days/year) +$600 gas=$1,500.

[some seeing eye]

It's good for people to ask these questions and develop an intuitive sense of what's possible.

Solar is the future, battery efficiency is improving but conservation and efficiency makes them work. Dinosaur plant fuel is cheap, liquid fuels are easy to transport, we're addicted to inefficiency.

If people are interested in solar and other homebrew energy systems, stop by the Alternative Energy Zone camp - they have tours.

[much2naughty2]

I wouldn't miss taking a tour of your camp and seeing what folks have come up with. But..

Solar is the future, battery efficiency is improving but conservation and efficiency makes them work. Dinosaur plant fuel is cheap, liquid fuels are easy to transport, we're addicted to inefficiency.

is nonsense.

Solar has been around for decades, and unless heavily subsidized, it's not cost effective, and won't be for many decades to come. Do you really think you could power the glitz lights in Las Vegas with solar. No, but then the answer would be conservation, another way of saying we have to unplug all those light and just find our way around in the dark with solar powered LED flashlights. Now that's conservation that works.

Batteries have and will continue to improve, but not to the exponential scale, efficency and size to make them practical in large scale application.

I'm a long time fan of solar power, but only in practical, cost effective application, not dreamy land nonsense. Sources like hydro, nuclear, coal, natural gas, are the future for the next century, like it or not.

[phil]

> go and calculate how many batteries you'd need to equal what a
> $900 generator will do.

So fuel is free now? We're comparing apples and oranges. You're looking at the cost of a generator as if that's the last dime you spend. You don't need maintenance, you don't need filters, you don't need fuel? Pablo's point appeared to be that over time, the cost of keeping the generator running costs more than using batteries. I may have misunderstood, but I don't think the price you pay for the generator set is the end of the expenses.

> The energy density of gasoline is 50 million Joules per Kg.

Gasoline is, so far, the cheapest way to power mobile units - cars, trucks, etc. That's why this country is in the straits it's in. Electricity is cheaper for homes and immobile uses or we'd all be burning gasoline in our home generators. But that's not the issue at Burning Man, where we can calculate our energy needs ahead of time, charge up the batteries at home at night when it's cheapest, and haul the batteries out to the playa where they discharge all that stored energy. When you get to the playa, the use of batteries is pollution-free. Of course, we burned coal to get the electricity, and we burned gas or diesel to get to the playa. But I suspect it's more energy-efficient to charge the batteries at home and discharge them on the playa than to pay to haul the generator and the fuel out to the playa.

> If you can get more than 3 years out of a lead acid battery, using
> and storing it as you would for BM, you're doing great

Louise and I have had one battery out there for five years, one for longer but I can't remember when we bought it - maybe ten years - and one for three. Our 10-year-old battery is an 18 ampHr battery with built-in inverter and built-in jumper for starting cars. We use it to keep our camera and rechargeable batteries going, and hand it around at the end of the event for others to use to jump their dead batteries. Our advantage is that we use our batteries year-round.

I have wrecked batteries, but not because they were on the playa - I just didn't keep them charged and use them year-round.

> You must make a case by case analysis, of each installation, before
> you can state for certainty which is best.

I guess I'm missing that part with regard to generators. It's just assumed they'll last on the playa for 10 years for a total cost of under a grand while batteries will be wrecked on the playa within a few years, costing a few thousand dollars. My big hundred+ ampHour batteries were under a hundred dollars apiece at Costco. I don't remember the cost of the 18 ampHour, but it was more because it has the built-in inverter and a solar panel that I use to keep it charged year-round.

> Do you really think you could power the glitz lights in Las Vegas
> with solar.

Are they using personal, gas-powered generators like the Honda i2000 (whatever the model number is)? No, they're using coal, aren't they?

This is Burning Man for a week. It's not your home where you'll need power forever. It's not your car where you'll need energy on the road and quick refills every 400 miles for as long as you own a car and drive. It's a special case where you know what you'll need for a week - how much food, how much water, how much energy - and you can bring it all with you.

Getting off track with using batteries for powering Las Vegas is as pointless as claiming you should run your Honda to power your house and your car. Straw man.

Where's the analysis for using generators on the playa?

[kman]

So much would a battery bank cost (and weigh) that will run an air conditioner, lights, fans, refrigerators, and charge small batteries, etc., for the full week of the run?

Can your average burner transport vehicle handle the extra weight on top of everything else?

That's the real question here. There's no doubt that a bank of batteries is better for the environment. There IS quite a bit of legitimate doubt that today's battery technology is up to supplying the power needs of a BM camp the way a fairly inexpensive generator can.

[Token]

OK, starting with next year I'm bringing out top o the line BP Solar pannels and leaving the Hondas at home!

[much2naughty2]

Better stick with the Honda Token.

No Phil, generator fuel isn't free, Perhaps you should reread my post, as that's why I added in $600. 2 gallons a day X 10 days X 10 years, X $3.00/gallon. Yes, I left out the quart of oil every year, and the spark plug every five. Let's put in an extra $50 for those over 10 years. 10 year lifecyle is based on personal experience, and they will likely last much longer.

Where's the analysis for using generators on the playa?

$900 generator(10 year life cycle x 10 days/year) +$600 gas=$1,500.

+$50 oil and spark plug.

You're right about this one Phil. Bringing a generator out to BM to charge your camera and flashlight isn't very efficient. You're the one that started this thread suggesting batteries were always better than gas or deiesel generators. I didn't know you were only talking about flashlight and camera batteries. Most of the discussions about generators assumes loads for thigs like AC units. Your 18 amp hour battery won't run an AC unit very long.

Uh ya, like I said, if you're only using your battery for BM, and storing it the rest of the year, it won't last long. But as you said, you use and maintain it year around.

Are they using personal, gas-powered generators like the Honda i2000 (whatever the model number is)? No, they're using coal, aren't they?

No Phil, they aren't using coal fired, likely using hydro power, hence the big dam east of Las Vegas.

kman,

So much would a battery bank cost (and weigh) that will run an air conditioner, lights, fans, refrigerators, and charge small batteries, etc., for the full week of the run?

At least 3 tons and probably over $10-15,000.

[kman]

kman,

So much would a battery bank cost (and weigh) that will run an air conditioner, lights, fans, refrigerators, and charge small batteries, etc., for the full week of the run?

At least 3 tons and probably over $10-15,000.

Yeah, I'm definitely going to need a bigger Prius. Oh, wait...

[Token]

I dream of the day when I can buy solar for a buck a watt.

Been dreaming for over a decade but it ain't gonna happen anytime soon.

Too much profit in this when it is tied to cost of electricity and what home owners are willing to pay on a 15 year break even cost.

The irony is that solar panels are made from one of the most abundant elements on the planet, the technology is all figured out and the one thing holding back mass production is greed.

So Phil, go protest Shell, BP, Mitsubishi, Kyocera, Sharp and the other fat fucks making billions at the expense of worldwide quality of life.

/hippie fucking tree hugger rant

Fuck, I hate it when someone mellows my harsh!

[weather man]

Starting THIS year, I'm just bringing hamsters.

[Token]

Starting THIS year, I'm just bringing hamsters.

Yeah, but how many kilo joules per pound per day of feed do you need to bring?

[capjbadger]

Nahh... what you do is get "volunteers" to pedal bikes at your " interactive art project" that drives some blinky light things*.

-Badger

*Bulk of power going to battery bank of course...

[ygmir]

Starting THIS year, I'm just bringing hamsters.

Mr. Geer? Is that you?............

[phil]

> You're the one that started this thread suggesting batteries were
> always better than gas or deiesel generators.

I just re-read my post, and I'm missing where I suggest that. The lead statement by Pablo of treehugger.com is that "you have limited amounts of gasoline," and it's cheaper in the long run to buy batteries.

> Most of the discussions about generators assumes loads for thigs
> like AC units.

I'm seeing more discussions about lighting up LEDs all night and running sound systems. I'm not seeing most discussions about running air conditioning.

Since I'm not saying batteries are always better than generators, another straw man, let's get back to the point: Generators are not always the best choice for power on the playa. Since we're on the playa for a specific time and with planning will know our power needs in advance, batteries may turn out to be a better buy than a generator. In some cases, they will be a better option than a generator.

[kman]

> You're the one that started this thread suggesting batteries were
> always better than gas or deiesel generators.

I just re-read my post, and I'm missing where I suggest that. The lead statement by Pablo of treehugger.com is that "you have limited amounts of gasoline," and it's cheaper in the long run to buy batteries.

> Most of the discussions about generators assumes loads for thigs
> like AC units.

I'm seeing more discussions about lighting up LEDs all night and running sound systems. I'm not seeing most discussions about running air conditioning.

Since I'm not saying batteries are always better than generators, another straw man, let's get back to the point: Generators are not always the best choice for power on the playa. Since we're on the playa for a specific time and with planning will know our power needs in advance, batteries may turn out to be a better buy than a generator. In some cases, they will be a better option than a generator.

Solar (and batteries) makes a lot of sense for small things like LEDs, but I don't know about sound systems. A sound system capable of hosting a "small" 50-person dance party on the playa is going to be a 2kilowatt system, conservatively, many are a lot more than that. Can you run those all day and all night off a battery bank (that weighs less than a ton or three) for a week?

[much2naughty2]

My appologies Phil, I reread you first post and you were just stating what Pablo wrote. So again, appologies, he's full of BS, not you.

[phil]

> he's full of BS, not you.

Oh, thanks!

:->

[teardropper]

I'll be using a 64 watt panel to power two 225 amp/hour golf cart Trojan 6volt batteries. Probably more power than I need, and I expect to share some. But I'm only using lights, mostly LED's, a couple of pumps and music, but not a sound system. It's not cheap but I would have more in a $900 gennie and gas. And Phil is right, if you take care to keep your batteries charged when not in use, they will last at least 5 years. If using A/C you will need a gennie.

[daveclay]

I'm struggling with the decision for my art project as well...

I have 120 RGB LED modules, each pulling 100mA at idle to 300mA at 6V when reacting to sound or movement. According to my calculations, that means:

120 x 200mA average = 24A, x 10 hours/night = 240AH/night. Splitting the power up between two batteries gives me 12A per battery, 12A x 6V = 72 watts per battery. Over 10 hours of night = 720W/night, and 120AH/night, being pulled from one battery.

If I assume 7 good hours of sun, I need to charge 720W/7 hours = 103W/hour of solar power to charge a battery. The cheapest panels I've found are 5 x 50W solar panels at $125 per panel, plus two deep cycle 6V batteries.

The biggest problem I've run into is that there aren't any solar chargers that take 12V input and charge 6V batteries. That leaves me with using 12V batteries and voltage regulators for each LED module, wasting 15-20% of my power as heat, and I'd have to take that into my power consumption.

I'm also currently in NYC, which means shipping the batteries and solar panels along with the project, and the cost of the solar panels, charger(s), and batteries...

From the point of view of cost and expertise, a generator seems like a much simpler and cheaper solution, including gas (biodiesel?)

Don't get me wrong, I'd prefer renewable energy both from my own sensibilities and ideals. But coming from zero knowledge of solar, and looking at my options, it's a hard sell.

Unless someone here has a silver bullet for me. Anyone?

[Token]

What are the LEDs, 3W Luxeon or Cree? Sounds like a lot of juice per LED.

At 6V 300mA, each LED is 1.8W. If all 120 burn constant full on its 216W.

You will need at least that much in solar panel power plus at least 4 6V 100+ Ah batteries and a charge controller.

Your calculations are good.

All that expensive gear just to get 200W of power.

[teardropper]

Would the option be to run the gennie all night to get 200 watts, or use a gennie to charge a couple of 225 a/h 6v batteries? I agree that if you have to buy it all new it is expensive. I already had the panels and controller for mine, just needed the batteries, $80 each at Costco. But I amortize it over the life of the batteries, 3-5 years and it looks better. Kind of like how I figure for my RV.

[some seeing eye]

Deveclay for specific solar projects, like the LED lights, you might surf over to the http://ae-zone.org/ and join their listserv. Note that the listserv submitting email addresses are in the clear, so use a disposable gmail with good spam filtering. Ask there to partner with an experienced designer, maybe they can transport the heavy stuff from Reno or the Bay Area. (You also might need to camp by your system to keep it from getting stolen)