Save electricity with your gas-guzzler

Ok, so we all know that you couldn't possibly be using all that power that your 5.4L Truck, or your 5.9L Van is making, but then where is it going? And how can we reclaim some of it? In this Instructable I will show you how to save electricity, and also be ready in case of an emergency.

Step 1 Supplies

Ok now we will need supplies

-Truck, car, van, riding lawnmower (no, I'm not kidding, some of them actually have 12v sockets!), etc.
-Battery jump starter/ battery booster pack/ rechargeable 12v battery thing (with cable to charge in car)
-12vdc to 120vac power inverter (mine is only 200watts)
-Lights, chargers, other things that use power (must total less that inverter's output, watts=volts x amps)

Total cost should be about $25,000, or only about $15-40 for inverter and jump starter.

Comments

[bballman2888]

You could use a larger inverter to power just about anything you want. I have a 16000W peak 8000W continuous running inverter i use with my marine battery instead of a generator. I mostly use it to run my 7" angle grinder out in the woods when I'm runnin scrap metal. works pretty good. People need to be careful though because most inverters out there are modified sine wave and are a lot harder on electronics. Pure sine wave inverters (the really good ones) almost match the wave frequency of the power you get from the utility company, but they are normally much more expensive.

[twocvbloke]

A better tip:
Buy a vehicle that is actually more efficient, rather than something with an engine greater than 2 Litres, that way you get more power to the wheels and less waste out the back end... :)

[PhantomOfHeat]

It might work out better getting a second battery from a junk yard and charge that with a disconnect switch and a voltage monitor to see the charge and the capacity should be larger than the jumper pack. If the kill switch is ran in line with a relay that has the on field switch ran to the acc on it will prevent it from charging when the engine is off with the key out.

[Roger4Wheel]

For those of you who would do this in lew of buying a backup generator (for cost or whatever reason), you could do the same thing with a rebuilt automotive alternator (under $50.00 for my Ford) and a regulator.

Just hook them up to your lawnmower.  If it's sitting on a smooth survace (not mowing grass) the 5 hp or greater gasoline motor will easily charge a car battery, and probably more efficently than the full size V8 in the truck.

Of course if you don't have an appliance with a gasoline motor (mower, rototiller, powerwasher, etc.) then this tip isn't for you.

[vtvtvt]

Using a car engine to generate electricity with it's alternator to charge a jump starter will cost far most in gasoline that it would cost to pay the electric company for electricity to do the same job. At least 3 to 5 times as much.

[NRen2k5]

- I think this'll ever-so slightly reduce your gas mileage, so technically you're kinda paying Big Oil rather than the electric company. - The items you used in your demo aren't big energy suckers either. The real big ones are your washer and dryer, TV, oven, toaster, coffee maker, microwave... generally anything with a heating element or a fairly powerful motor... These all draw more than 100W (some of them much more) - Booster packs are meant for just that: boosting - a very short and heavy current draw. They shouldn't perform amazingly for this sort of long duty cycle, low-current use. - Still, looks like a good idea for emergencies.

[aaronjehall]

Good point. Living in the north, I've been planning something similar to this using my 1981 Chevy work van. If the power goes out in the winter, it sucks. Problem is, I need over 1500 watts; most heaters of any count being 1500 watts. My plans did not include the portability of a battery box, tho. I just wanted a makeshift mobile home to sleep and keep warm in.

[LinuxH4x0r]

Some of them can be plugged directly into 12v power and still work.

[Derin]

ahhhhh in the hardware store everything i want is miles off my cash range i have about $100 but all the good stuff is more than $150!D:

[aaronjehall]

Yeah... How much would a 1500w power inverter be?

[LinuxH4x0r]

Around $100

[Grey_Wolfe]

It's too bad the vehicle wastes like 80 percent of the fuel, too. (Well more like 82%) But a nice way to save a buck or two, as long as you don't kill the alternator.

[Derin]

most alternators are rated for 100A,some truck ones may force 200A

[aaronjehall]

You can always get an overrated aletrnator as well, like what a car with a high watt stereo system would need.

[LinuxH4x0r]

Yeah, it only gets around 18. I don't think it puts that much load on it to kill it, or even shorten it's life.

[jimpsolar]

I see here that jasonfehrs states you will use one hp per 25 amps. Can we take this one step further and calculate into amount of gas per amp? Not sure why this is so because the alternator is always turning. Where does the extra resistance come from when it is charging? I plan to setup a couple of marine batteries and charge them up on my 30 minute commute and then plug a cord and power strip from my house to the car at night and run a few small power items. Lights radio etc. This may sound like a pain for some people to do but we need to do something. (its a pain to dig into my pocket for money to pay for energy) I look at my vehicle in a new light, both for transportation and power generation.

[xaenon]

The alternator creates magnetic fields in both the field and stator coils, which tend to resist the movement of the stator. The harder the alternator works (ie, the more current it must produce), the stronger the fields and the greater the mechanical resistance. In the days of carbureted cars, you could actually hear the engine's idle speed drop when the alternator went under a heavy load - like when jump-starting a car with a dead battery, for instance. Modern engines with their electronic controls can adjust idle speed to compensate for various loads, so it isn't as noticeable any more.

[nubie]

If you want to save energy you can use a drive-shaft mount alternator to charge as you coast or stop:

http://www.jalopyjournal.com/forum/showthread.php?t=89519&showall=1

Normally used on hot rods or racing vehicles, you can put a closed throttle switch on your vehicle that will turn the alternator on only when decelerating. This would use truly wasted energy that would otherwise be converted into heat by the brakes.

[LinuxH4x0r]

Sounds like a good idea for the electric car I'm working on

[Rishnai]

I knew a guy once in Arizona, never hooked up the utilities. He had a bunch of brake lights on a string that he hung around the living room like Christmas lights, and at night he would pull the battery out of his truck and hook them up. Lit the whole room. Once he'd done a little reading and his kids had played a little, they disconnected it and went to bed. He had a little generator that they ran once a day to chill their fridge, then kept it shut all day except for one flurry of motion when his wife would pull out all the fixin's for dinner, and then cook it on a camp stove. A little off the wall maybe, but they were nice people.

[Grey_Wolfe]

I live in Arizona, lol. Not an overly bad idea, cept maybe the fridge. Well have to get the seals around windows and doors a bit better before we go killing the swamp though. That's Beverly Hillbilly livin' there. lol

[LinuxH4x0r]

Maybe you could make a solar ice maker...... I'm going to try to make one sometime

[Grey_Wolfe]

I haven't thought about one of those in a long time. Excellent idea, thanks. Have you been able to find any good plans? Maybe here on the site?

[Grey_Wolfe]

What about using one as an alternate to a standard condenser to make a more green AC unit?

[Rishnai]

One nice thing about Arizona is that ya'll get a dry heat, so swamps work. Here in Colorado they usually work, but this year it's been too damn wet. It's like I'm back in Misery (Missouri).

You shoulda seen the summer me and my dad's family spent in a settler's cabin, with all the original 1960s features, including hot and cold running vermin. That was hardcore hillbilly.

[Grey_Wolfe]

I didn't notice the 'hot and cold running vermin' part before. But it make me feel warm and fuzzy. lol

[Grey_Wolfe]

That 'dry heat' thing is only partly true. Right now the thermostat's reading 80 (in the cool part of the house), and the swamp's yet to be turned off in the last few weeks. But that's the way of monsoone season here. We're running about 40% humidity during the day right now. Nowhere near Missouri, but enough to make the swamp fairly ineffective. But during about 8 months of the year, the swamp does work pretty good. And it's much cheaper than AC. Costs me about a third to cool this house compaired to my mobile, and at three times the footage.

[Rishnai]

Oops, 1860s, not 1960s.

[jasonfehrs]

Although not very important in such a big engine as you mentioned (5.4L, 5.8L), it is worth noting that the more electrical power that is generated by the alternator, the more horsepower the engine with be derived of. An alternator typically takes about 1 HP (horse power) for every 25 amps of power generated. So, a 100 amp alternator will require about 4 HP at full output. Most alternators do not operate at full output for very long. Not a very big strain for a large engine, but a big consideration for the compact crowd with engines only outputting around 100HP. Another thing to consider is that the AC compressor typically using around 10 horsepower. As we all know, the more horsepower that is starved from the engine, the more gas you use.

[itwasalan]

I was thinking of something like this the other day. Nice work. I'm off to the auto parts store.

[LinuxH4x0r]

Thanks!

[LinuxH4x0r]

actually the leds use much less, its just the efficiency of the circuits that power them.

[velojym]

Wow. Lots of repeated posts here. While I'll agree that it'll be far less expensive to charge the jump battery from the grid, a centralized grid has the interesting habit of going down from time to time. While a generator is on my shopping list, our recent tornado outbreak had me running a 750W inverter from my fullsized Blazer into the house to power a small TV, my notebook computer, and my network hardware. Using a 5.7 V8 as a 750W generator was horribly inefficient, but it was power, and the massively centralized grid had failed on us. Of course, keeping one of those jumpstarters in the house would seem to be a very good idea, for the same purpose. There's a lot of kicking and biting going on here about piddling points, in my opinion. The original poster has already stated that he hasn't tested this for efficiency, and the bickering has become pretty repetitive. See the "be nice" policy below.

[LinuxH4x0r]

Yeah, I realized that after I made this. If I had to do this it would be even worse. I have a 200w and a 400w inverter, and a 5.9 liter engine!!! (actually it gets better than my 5.4! 0_o ). Thanks for the support. Most of the regulars here are nice, but sometimes...... Thanks!

[Lithium Rain]

I like it.

[LinuxH4x0r]

Thanks!

[Big Bwana]

Now LinuxH4x0r If you where to use a thermocouple and utilize the waste heat going out of your rad this would be a great instructable, or even a peltier junction type device, just like the ones found in a portable coolers, if you apply heat. (( temp difference, ok one side needs to be cooled as well but a heat sink is normally enough )) they produce power.... But I do use your idea since it is portable, and handy to charge cordless tools , while going from job to job, and I hate showing up and find out the battery is dead and waiting an hour for them to charge, and the very small amount of fuel it uses, is a lot less then the amount of fuel the tow truck uses to come and give a boost when you've accidentally killed a battery after forgetting to turn off your inverter.... ((I Wouldn't know any thing about that .........))

[LinuxH4x0r]

Its not really a gas saver, but it sure is handy! Thanks!

[Vailhem]

What about using an old car alternator for a generator at your house? Like, a design to hook an alternator up to blades for a windmill? or, if you live by a stream, a paddle or something? I've been wondering about this for a while, and when I get some time, I plan on working on it. Refurb'd alternators are $25? at Pepboys. All you'd need is a pole, some blades, and a source to even out the load. ?

[LinuxH4x0r]

Yeah I've been wanting to do that. This is mainly intended for long trips and stuff like that. I hope to have some sort of generator going this summer Thanks!