The founder of Blue Rhino propane-tank refill stations has a new product.
"Callahan has invented a football-sized electric water heater with patented technology he believes could save everyone lots of water, energy and money. No more running the water for a minute before it?s hot enough to use, no more plating parts, no more scalding, he promises."
Good from the first drop.
I fail to see how this is any better or worse than a similar unit that uses conventional resistance elements which uses the same amount of energy. Resistance heaters are 100% efficient too.
I read the patent app and some stuff about it at the company's website. Apparently, the lack of heating electrodes means less surface area for scale to accumulate upon. That might also be a factor in its comparatively small size, even for a tankless heater.
The large tank is not efficient. Depends on how much insulation used, easily added on electric model.
Greg
Rhino crooks. Gas went up then down, but propane only went up. They forgot to come back Down Crooks.
I but propane at Walmart, $ 6 cheaper than blue rhino.
Greg
I should have owned ferrel gas partners, instead of embridge energy stock. I could have been a crook on the take.
Greg
I'm a bit suspicious of a tankless (near as I can tell, it's tankless) electric water heater from a guy who sells about $16 worth of propane for $23 to $35. If it's truly a tankless electric and it has a better electrical energy input to water heated ratio.....then it might be more efficient as he claims.
But I'd have to see the numbers......electric energy input and water flow (gpm) & temperature rise.
If he's waiting a minute for hot water then he's got ~80' of 1/2 copper tube or ~40' of 3/4 copper tube. (that's the length of tube that holds a gallon of water) . Hot water flow assumed to be 1 gpm.
His comment "no more running the water for a minute before it=92s hot enough to use" seems more than a bit unrealistic.
Resistance heaters are only 100% efficient (electrical energy input =3D mass of water x temperaure rise) in a tank water heater situation AND where the water has sufficient residence time.
cheers Bob
There's such a glut of nat gas that unless producers drastically cut back storage capacity will be exhausted come October.
The only way I've ever heard of seeing a lower propain price is to switch vendors.
m
Regarding gasoline, for example, "rocket up, feather down" is justified by the math.
When a gas station refills his tanks and the refill costs him ten cents a gallon more, he has to increase his retail price accordingly, not only to recover this price increase, but to lay in a surplus in anticipation of the NEXT delivery.
If the delivery truck charges him ten cents a gallon less, he still has to recover the cost of the gas in his storage tanks. That is, if his storage tanks are half full when the tanker truck pulls up, he can only drop his price by five cents. Then with the next fill-up, he can drop his retail price by 2.5 cents, and so on.
Resistance heaters are 100% efficient regardless of where they are or what the residence time of the water is.
100% of the electric energy is converted to heat. Longer residence time for the water only means it gets hotter. Flow the water through at rocket speed and the water might go up only .01 degree, but 100% of the electric energy is converted to heat. Some amount of the heat from the water is then lost through the heater to the ambient, but 100% is always converted to heat. And increasing the residence time, ie decreasing the flow rate, would only make that lost heat greater, because the temp of the heater would be higher.
Good point, my thinking was faulty..... Because there is no "exhaust or flue", there is no way for energy to leave the electric water heater except through the water. A very small amount (insignificant I would imagine) could leave through the body of a poorly insulated tankless unit but that's splitting hairs.
btw on gas fired units 100% of the gas energy is turned to heat but some goes up the flue.
Additionally, 100% efficiency means that 100% of the input energy goes into the heated water. Electric units are very, very close to that. Only the energy lost to the surrounding environment does not go into the water.
There is no way an uninsulated electric water heater could be considered "100% efficient". Merely turning 100% of the electrical energy into heat is meaningless if only 50% finds its way into the hot water.
Gas fired units are different animals. The flue gases can contain a fair amount of energy in a convention gas water heater. Hence the desirability of condensing combustion.
cheers Bob
In engineering and science it's known as hysteresis. In any kind of control system, hysteresis prevents wild swings and oscillations. The thermostat for your home relies on it as does the power steering in your vehicle. I'm no economist but I'll guess there is a term used in that field that means the same thing if not the same term. ^_^
TDD
I take the tank to U-Haul to get it refilled or buy whatever amount I feel I need at the time. ^_^
TDD
You are paying for convenience. You have noticed that prices in "convenience" stores are higher than the prices at much larger retailers at longer distances from your neighborhood? Could you imagine what gasoline for your car would cost if you had to swap tanks every time you needed fuel and the fuel tanks were in locked cages at the corner store? O_o
TDD
Have something to add? Share your thoughts — no account required.
Ask the community — no account required