Inverter vs Generator

[headquarters]

Hi all,

I had a question to pose to the masses. This won't be my first trip to Blackrock however I am trying to do something I've not done prior years. As far as power before we had a camp which utilized a deep cell battery and LED Christmas lights. We charged the battery with a solar panel (small one) that a friend had. We didn't get much life out of the battery and the panel didn't provide much juice to charge it. That all being said I don't even have the solar panel anyway.

That leads me to this year. I wanted to have some led Christmas lights (or regular but really want LED). I also want to power a small stereo. Not the smallest of little cd player guys, but a small home receiver/speakers with at least an aux in to play an old iPod.

We're trying to have a nice neighborhood camp this year, and my wife is having a birthday we are trying to celebrate. Nothing to crazy.

We will probably only need the lights a few nights, as other times we'll be going out and exploring or going to bed early (what old babies we are!).

I've been looking at lower cost generators to provide the electricity for this, and have been concerned with transporting them as well as their noise.

My other thought was to bring a ~800-1500 watt inverter and hook it up to my rental cargo van. For what it's worth we will have 2 cargo vans between the 4 of us that are going. So I guess in the pitiful event that I kill the battery I would be able to jump it with our other van.

My experience with an inverter is limited. I've read that you need to attach it straight to the battery as well as have an inline fuse on the DC side by the battery. My real questions come from an economical standpoint as well as an environmental standpoint (local and in general). I imagined that you can run the van while we use the inverter and never worry about the battery draining? Of course we would be using gasoline. Is that reasonable? Does anyone have any experience in this type of thing as to how long you may need to run the engine / hours we have the stuff running?

Would 12v lights be a better choice and just have the inverter for the stereo? Are there any fun places that sell 12v lights or instructions?

Any feedback on what sounds like a better idea?

At the moment I'm leaning toward the inverter because I'm really adverse to having a loud generator running. I can bring some extra gas for the van of course. What do you friendly people think? Thanks!

[FIGJAM]

You can find solar leds all over the place for about $20 a 50 light string.

They last all night.

[headquarters]

You can find solar leds all over the place for about $20 a 50 light string.

They last all night.

I understand that, although it doesn't address the stereo.

Thanks though, I will check them out.

[trilobyte]

Get a 'whisper quiet' generator, or (less expensive) build a baffle to muffle the sound for your camp (and neighbors) on a small regular generator.

While LED lights may not seem like much of a drain, that usually turns into a few strings, and then with a stereo and over the course of several nights you're probably looking at having to run the vehicle several times throughout the week or risk draining it dry.

[unjonharley]

\\

I have a old Sony Boom Box.. I use to amp an Ipod/walkman..A 5ah battery pack for the player and a small deep cell for the boom box..The battery pack lasted all week and then some.. The deep cell had to have a little boost day four.. I had left it on over night twice.. I have a cig lighter plug in that reduces 12v to 4.5 for the disc player.. For the Ipod I have a 75watt inverter that plugs into the van, The boom box also take d cell batteries. When cranked this set up can be heard a block away..

[Trishntek]

I have a 125Ah deep cycle 12V battery I take camping with an inverter. It runs a 40W stereo, two 25W lightbulbs and a string of rope light for 4 hours per night for three nights and is still 30% charged when I return home. I use a 750W inverter for camping.

For the playa, I have a much larger solar array which is way more than what you seek. You could get a little 40W solar charger at Harbor Freight which would probably recharge your battery sufficiently to prevent complete discharge in a week. I'm not saying it would fully recharge it everyday, but it would be enough to keep the battery from going dead.

OTOH, a small generator would probably cost a little more, plus gas and oil. The noise can easily be mitigated by simply placing it between two vehicles or other "walls" which would direct the noise upward rather than laterally. We take a 3kW genset just for backup and only use it for power tools and electric coffee maker.

[ConnieH]

My experience with inverters pushed us toward a generator this year - inverters aren't very efficient and use more battery power than if you had dc lights and dc stereo hooked direct to the battery. We tried to power a 60 foot string of led rope light and a small cd boombox on our 800 watt inverter and it only lasted a few hours. From what I understand, inverters run more efficient if the load is close to the capacity of the inverter, so we tried a 150 watt inverter and it lasted a little longer, but still only about 4 hours on an 80ah battery. If you could find a boombox that takes batteries, I'm pretty certain you could hook it direct to your battery since it's already set up to run on dc - anyone have experience with that? We needed more power for more lights and bigger sound, so we bought a Yamaha EF2000 genny - the thing is uber quiet and a gas sipper, but wasn't cheap ($650 used).

[headquarters]

Thanks for the input all. I went with a generator, and am going to build a baffle for it to keep the sound down.

[Zang]

Suspended Animation uses both! We have an inverter, and charge it with our generator. The advantage is that we can run the generator full force into the inverter to charge it, then trickle power off the inverter for the rest of the day. This means we don't run the genny 24/7 just to power a string of lights or a small stereo at a fraction of the genny's output. It also means we don't have to worry about keeping the genny fueled, cooled, and baffled. (We did built a custom baffle for it, to be neighborly and all, but it's not as much a worry when it's only running for an hour at noon.)

We run power to our kitchen, lights for our lounge, show lights for our stage, lights for our camp sign, and our full sound system off this inverter -- and have enough spare capacity that we run lights for our neighboring camps as well.

So all in all, I'd say that inverter + genny is the optimal solution.

[headquarters]

Suspended Animation uses both! We have an inverter, and charge it with our generator. The advantage is that we can run the generator full force into the inverter to charge it, then trickle power off the inverter for the rest of the day. This means we don't run the genny 24/7 just to power a string of lights or a small stereo at a fraction of the genny's output. It also means we don't have to worry about keeping the genny fueled, cooled, and baffled. (We did built a custom baffle for it, to be neighborly and all, but it's not as much a worry when it's only running for an hour at noon.)

We run power to our kitchen, lights for our lounge, show lights for our stage, lights for our camp sign, and our full sound system off this inverter -- and have enough spare capacity that we run lights for our neighboring camps as well.

So all in all, I'd say that inverter + genny is the optimal solution.

That's funny, I was eating dinner and the same thing occurred to me. Get a deep cell battery, charger, and inverter and charge the battery with the generator. A splendid solution. You mentioning it confirmed that it was a sweet idea! Thanks

[ConnieH]

Suspended Animation uses both! We have an inverter, and charge it with our generator. The advantage is that we can run the generator full force into the inverter to charge it, then trickle power off the inverter for the rest of the day. This means we don't run the genny 24/7 just to power a string of lights or a small stereo at a fraction of the genny's output. It also means we don't have to worry about keeping the genny fueled, cooled, and baffled. (We did built a custom baffle for it, to be neighborly and all, but it's not as much a worry when it's only running for an hour at noon.)

We run power to our kitchen, lights for our lounge, show lights for our stage, lights for our camp sign, and our full sound system off this inverter -- and have enough spare capacity that we run lights for our neighboring camps as well.

So all in all, I'd say that inverter + genny is the optimal solution.

How long can you run all that on your battery through your inverter? What are the sizes of your battery and inverter? We tried 150' of rope light, two compact florescent black lights and a small cd player through our inverter/battery and it only lasted an hour before pooping out.

[Trishntek]

Not only the battery but the efficiency of the inverter must be considered. The 1kW pure sine inverter on our solar array only uses 3% of the power with an 80% load. Some can use 10% or more.

If you are seeking 12V, it's better to go with two 6V golf cart batteries in series. You can get the 325Ah for around $100 each. The $$ per watt is a better deal that way. I have 4 of them on my solar array which is wired for 24V at 325Ah. That is 7800 watt-hours of storage.

[Trishntek]

dbl post

[ConnieH]

Not only the battery but the efficiency of the inverter must be considered. The 1kW pure sine inverter on our solar array only uses 3% of the power with an 80% load. Some can use 10% or more.

If you are seeking 12V, it's better to go with two 6V golf cart batteries in series. You can get the 325Ah for around $100 each. The $$ per watt is a better deal that way. I have 4 of them on my solar array which is wired for 24V at 325Ah. That is 7800 watt-hours of storage.

Whoa...you just blew my mind...I have so much to learn!! 325ah is awesome, I paid about $80 for my 80ah 12 volt deep cycle.

[FIGJAM]

AEZ?

http://ae-zone.org/category/energy/

[SnowBlind]

Not only the battery but the efficiency of the inverter must be considered. The 1kW pure sine inverter on our solar array only uses 3% of the power with an 80% load. Some can use 10% or more.

Yes, 3% is awesome. Of course the pure sine inverters are generally more expensive, and need more sophisticated electronics, so I guess it's not surprising that they have better efficiency too. As you said, most of the cheaper modified sine wave inverters will probably have closer to 10% - 15% loss.

[SnowBlind]

Whoa...you just blew my mind...I have so much to learn!! 325ah is awesome, I paid about $80 for my 80ah 12 volt deep cycle.

Keep in mind that you are comparing apples and oranges (12v vs 6v). You'd need two of those to get 325Ah @ 12V. Still a better price per Ah though.

[Zhust]

Two links to consider.

A friend of mine asked me about Voltaic Systems. They sell ready-to-use kits that combine solar panels, lithium-ion batteries, and USB charging ports. No option they sell gets you to 120-volt output, but it is a way to not think and get something that can charge your camera batteries and a USB AA battery charger (e.g. this one). Being a DIY person, this seems absurdly expensive.

The other link was for my Instructable comparing 12V DC LED strings to using an AC string with an inverter. The thing about bigger versus smaller inverters is their quiescent current — the amount of power they use to just be "on" without anything plugged in. A quick test of a cheap 100W inverter I bought 4 years ago indicates a quiescent current of 100mA which is pretty good. My expensive 300W pure sine Samlex PST-30S-12A has a rating of "<700mA".

In other words, the 100W inverter uses about 1 watt just to be on and the Samlex uses 8 watts. Both are rated at 85% efficiency. So to run 5 watts of LED lights, that's 5W / 85% = 5.9 watts; the cheap 100W would use about 7 watts and the Samlex about 14 watts. A big 90 amp-hour deep-cycle battery holds 90 amp-hours * 12 volts = 1080 watt-hours, but you really only want to use about 50% of the capacity, so figure about 500 watt-hours. It could run the lights for about 35 to 65 hours depending on the inverter.

[tink2011]

Thanks for such indepth answers regarding the gene/inverter/battery questions, as I've learned a lot from reading this string. I have a golf cart based mutant vehicle and have run the EL wire and the rope lights off of a dozen AA-battery packs hidden throughout the vehicle that I have to turn on and off every night. It's okay on the way out, but a PIA in the middle of a dust storm at 2 am when all I want is my pillow. So, I want to run it all off a central area this year. The issue is that I want more lights (LED rope lights and EL) to light the space ship. I'd like to be able to run more than 30 feet per run, and so I've read that I'll need 120v power to do that. Should I get an inverter hooked to a deep cell battery? If it only runs for 4 hours, that won't be enough to last me out on the open playa at night. A generator for such a small vehicle is impractical. Any advice?
P.S. I'm not an electrician, in case you couldn't tell...so go easy on me!

[gyre]

Inverters vary in efficiency, as well as efficiency curves (by load).

I don't know about needing 120v, but packs using small batteries can be replaced with D cell packs.
A central pack may run into issues with differing loads, but it will work.
The load issue can be dealt with.

[some seeing eye]

Tink, You can run more than 30' lengths of LED lighting on 12V. Connect in parallel rather than series. LED power consumption is very small, compared to incandescent rope lighting, and EL wire power consumption is much less than LED.

Suggest buying all 12V lighting, rather than converting DC battery to 120V AC, then back to 6-12V DC in the light strings and EL drivers. At home you can reuse the 12v lighting driven by a cheap 120V AC to 12V DC supply. Online and boat stores have DC lighting. The EL suppliers have fixed 12V drivers.

Find some burners in your area that know series and parallel circuits, wire gauge, power regulation, and can use a multimeter. Many of them hang out at places you can find on this list: http://hackerspaces.org/wiki/List_of_Hacker_Spaces or with local solar groups.

It's trivial to run all your lighting off an oversized set of main drive batteries, or from a solar charged deep cycle AGM boat battery. You can reuse the battery and lighting at home throughout the year.

A generator is overkill, unless you are running a very, very large sound system or a Dr Megavolt setup on your mobile rig.

[Father_Burn]

See my post in another thread:

viewtopic.php?f=278&t=51987&start=30#p804005

[ashleyjames222]

What kind of inverter i use for my solar panel

[CornMan]

Last year, I took a propane lantern and spray painted the glass globe with high temp red paint. That gave a warm light which went well with the cold light of the LED lights. We used a lantern with an unpainted globe in the kitchen carport.

[wkorthof]

Check the power use of your loads carefully. That's the real problem that most people run into.

Regular rope lighting is an incredible energy pig that will quickly drain your battery charge (inverter) or fuel (generator).
Regular incandescent rope lighting uses about 4-5 watts per foot; 150 feet = 600 watts (that's huge)
LED rope lights, by contrast, use roughly 0.5 watt per foot, so 150 feet = 75 watts---drastically better
Regular christmas lights (incandescent) also use about 10 times as much power as the LED substitutes.
Halogen work lights are another common and massive power hog. Switch to clamp-lights with CFL, or CFL work lights,
or LED work lights---again, you're usually spending 300 to 1000 watts for the halogens, versus 10 to 100 watts for the
LED and CFL options that work about equally well.
Usually, your sound system's power use is trivial; real power draw is usually about 1/5 or less of the rated wattage on the nameplate.

Yes the LEDs cost more, but why spend 10x as much on the power system and fuel (or solar/battery) to run it?

I bring large amounts of solar power to the Playa every year, and in order to have success with all our projects, I'm always
having to go around to remind people to avoid all of these common power hogs.