River Turbine

Water typically has about 780 times the density of air (if my math is right). That means that a small drag type or savonious turbine could generate some usable power. Not a lot, but usable non the less. Using 4 inch pvc for the floats and the blades gives us a blade set that is about 7 inches wide and in the drawing I made each blade set about 7 inches tall. But you could make longer if you have deeper water. If you make each blade 14 inches long and have two of them like the picture shows, then you should get somewhere between 2 watts and 300 watts. That is if the water is flowing between 2 mph and 10 mph. At about 5 mph you would get a consistent 40 watts. You could also build a few of these with those cheap treadmill motors. The motor could be housed in a wood box to keep the rain off and open on the sides at the bottom to let the belts connect. Multiple units could be connected in parallel to charge a battery bank.
So, the floats are just 4 inch pvc with end caps. The platform is 1/2 inch plywood painted with good marine paint. The generator is a small DC motor. The blades are just a section of the 4 inch pipe cut to length and cut in half and then slid apart. You could have a tail on the back so it always lines itself up into the water flow like a windmill would. Or you could have a rope that holds it into position. Also, if you slide the blades further apart from the axis, you effectively make a bigger blade set and can get much more power. But rememer that it will spin slower and the homemade wooden pulleys will have to be bigger. To see how to make a wooden pulley, check here and a lot more detail here.

So, if you have a river or stream on your property and the water flow is between 2 and 10 mph then you could use this. You could even use this for tidal as well.

How good is this? Well, let's say you get 50 watts on average, 24/7. And into a 12 volt battery that is about 4 amps. That is what a 60 watt solar panel does, except that is only about 5 hours per day. So you would need about 5 of those 60 watt panels that cost about $400 each. So, $2,000 worth of solar power PV panel equivalent. Don't under estimate continuous power. It can be very deceiving. And this could be built for $50 to $100 each depending on the motor you use or if you have one already.

Richard

Electric Cars and the Ultimate Battery

I was reading an article today on "The Oil Drum" called

Who Killed the Electric Gas Tank?

This article called about EEStore's super capacitor battery replacement. They are still working on it and it is controversial whether or not it can even work. It supposed to be about 52kwh at 3,500 volts. It is supposed to be charged in about 3 to 6 minutes. A couple of thoughts occurred to me.

First, they say we need 50kwh of power to get the range that everyone is used to - about 300 miles or so. Most electric cars today get somewhere between 60 and 120 miles on a charge. It isn't good to fully discharge lead acid batteries, so most home built electric cars could possibly go up to 120 miles, but the owner minimizes the trip to half that so that the battery life is extended. But, be aware that most people are fine with short trips per day. The average commuter drives about 30 miles a day. So, my question is, do we really need that kind of range? If we do, we could take a bus, train or a plane. Are we so spoiled that we just have to have a 300 to 400 mile range? Or is it just the brainwashing from the media that constantly compares electric vehicles to their gasoline alternatives?

The second thought was the amount of time to fill up. The assumption is that people wish to fill up their electric vehicle in the same time it takes to fill up a typical fossil fuel car. That changes as well. A big SUV takes longer than a Honda. And a small diesel car can take longer than a suv. That is because the diesel is foamy and topping it off gets pretty slow. But lets say the average is 3 minutes. The EEStore seems to shoot for that goal. So, that is 52, 000 watt hours from empty to full in 3 minutes. I don't know about you, but that struck me as a lot of power in a very short amount of time. If you did that charge in one hour from a 240 volt outlet, then that would take 52,000 watts of power at 240 volts and 216 amps. Most houses are setup with 200 amp service, so that wouldn't work. If you did that same charge in 3 minutes, or 20 times faster, then it would take over 4,000 amps. NOT GOING TO HAPPEN!!!

But, let's say that you only needed a 140 miles or less per day and you needed to top off the super capacitor at 24,000 watt hours. If you had 100 amps free to use in your house, then you could top it off in 1 hour, or a little over 2 hours for the full 52kwh capacity.

Most electrics drive maybe 60 miles a day tops and need about 10kwh up to 15kwh to replace that charge. Charging from any 120 volt socket, that takes about 7 to 10 hours. From a 240 volt socket rated at about 20 amps then you could charge that in about 2 to 3 hours.

But, assuming you need to top off the super capacitor at your house from empty to full and use that same 20 amp 240 volt circuit, it would take over 10 hours. So, the fast charge may not be an option, although a battery swap program would work pretty nicely.

Don't get me wrong, I like the idea of super efficient and cheap batteries. I just want to see very light weight vehicles and/or bikes and trikes for daily commutes. Something small like this could charge very quickly because there is nowhere near 50kwh of storage in it. A 24 volt bike battery with 10 amp hour batteries only holds 0.24 kwh. That means you could fill that size super capacitor 200 times faster. So, a super battery for the bike could be charge in 3 minutes, but not a big one for a car that gets 300 mile range. (Unless you get powered up at the nearest power plant)

Super batteries are nice, but striving for the ultimate 3 minute quick charge, while possible, is not at all practical. Probably the best you could hope for at a filling station is to get 10kw at a time. After 10 minutes of that, you only have about 1.7 kwh of charge, or about 6 miles worth of driving. (If 5 people charged at the same time it would be about 50,000 watts at about 200 amps.) And 6 miles for charging every 10 minutes isn't that great. Even if they double the power available to 20,000 watts, you are still looking at 2.5 hour charge time. If you went to 50,000 watts of power available then it would still take an hour to charge and only a few people could fill up at a given time.

It reminds me of Ean from the first Jurassic Park movie, "Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should."

Richard

Homemade battery

Sorry for the late post today. My friend and I were working on the homemade 6 volt batteries made from the recycled free forklift batteries. Each battery that we are making will be 6 volts, 650 amp hours and weigh about 300 lbs. This is way easier to move around when compared to 1,500 pounds or so. Below is a video of "tinning" the bus bar.

We took a type "L" 1/2 inch copper pipe and cut it to length and then smashed it with a hammer. Then we drilled holes for the bolts. We then put the thermal paste on the ends and heated the ends so we could apply the solder. Before it cooled we wiped the excess off to make it nice and smooth. This will ensure good contact with the battery terminals and will prevent corrosion. (the picture below is before the tinning)

These copper tubes can handle over 800 amps. Isn't that amazing? Most people think they have to buy specialty copper bus bars that are expensive and have to be shipped from some exotic place. Or you have to be an electrician to know where to get the bus bars. Well, copper pipe is cheap and sometimes free. In fact, almost any HVAC technician or plumber will have some pieces laying around that they would gladly give you.

Below you can see that I ground the lead bar on the battery nice and flat so it can make good contact and have lots of contact area.
In the picture below, you can see the whole battery all connected and being charged. Notice, it is just a welded frame on a tray and there are tabs at the top where "all thread" is used to tighten up everything.
We still have to clean up the outside of these cells and paint the battery tray. This is just a test to make sure it all fits. We have about 15 more batteries like this to make over the next few weeks. And remember, everything was free except the "all thread" and bolts and angle iron. So, cost of each 6 volt, 650 amp hour battery is about $4.

Please, let me know if you have any questions.

see ya tomorrow,
Richard

Power Outage Alarm

I know what you are thinking, "Why would I want an alarm to tell me when the power is out?" Well, I want to make one for the freezer. The hot tub is on the same circuit and I've had the circuit breaker trip and I didn't notice until the next day. Luckily I noticed in time.

I could design a circuit but it is a lot easier to use something that already exist if it is cheap enough. I plan on getting one of those plug-in rechargeable flashlights that light up when the power goes off. Then get a piezo buzzers from Radio Shack (the Source) and hook it in parallel to the light bulb. That way, the light comes on and the buzzer annoys us until we flip the breaker.

This would also work if the freezer is being run from battery and inverter. What happens when the batteries get low and inverter automatically shuts off? This would warn me to do something else. Nothing worse than losing a freezer full of meat.

And, of course, some people would use this as an alarm to let them know that power just went off while they are sleeping.

Richard

Depression Cooking Videos

A 91 year old grandmother shows simple recipes from the Great Depression era. When times get tough in the near future and we have to rely on food that we grow, the knowledge here could come in handy. This is just the first episode and you can find the rest here.



Richard