As the inventor , please allow me to clarify a few things.
I understand the skepticism when approaching an entirely new technology, especially one that is clearly disruptive and replaces what has commonly been used for decades. Your point is that our claim of using graphite heating elements, cannot be true. We do not use graphite heating elements. We do not use heating elements at all. We do not employ any aspect of heat transfer. Our technology (and our patent) is based on Direct Energy Resistance. This technology heats the water by passing a current though one or more pairs of graphite electrodes (which are not heating elements, but electrical conductors, which is why they do not get hotter than the water) , which excite the water molecules causing friction between the molecules, which results in the water heating itself. Same concept as a microwave, except we use a different method to excite the water molecules. Same method as NUCOR and other steel mills use to melt steel; pass enough current through the material (in this case water) and it gets hotter. So the is no latent heat - zero. Its like comparing a water proof toaster to a microwave. 2nd law of thermo does not apply here.
Since the electrodes don't get hot like heating elements, they do not get mineral deposition, or "scale" on them.
Rheem constantly makes misleading headline statements about they capacity. For example, they claim 4 GPM at 13kW. When you read the fine print, that results in a 20 degree temp rise, which unless you have incoming water at 90 degrees, is not going to give you a warm shower. The equation for all tankless is kW X 6.83 = temp rise (F) X GPM. You can see that their, and other units, follow this formulas as do we. You cannot beat physics.
I suspect some of you are thinking that this is a dangerous device; 1) Current only passes through one or more pairs of electrodes, creating a circuit, with no stray currents. However, we have added two grounding plates in the water chambers as a safeguard and we have passed UL 499 standard in our lab, which assures safety. Any and all units we ship will pass the $(( standard as certified by an outside lab, such as UL or TUV.
If you want to see the US patent, it is number 7,817,906
There are many reasons why people post projects on Kickstarter. Maybe some are desperate, we are not.
be an improvement over inline electric tankless water heaters, but lets be honest. Electric tankless systems are a novelty, up-sold by contractors to the impatient wealthy. They are not a replacement for the traditional tank system and MUST be used in conjunction.
Your marketing is pretty devious. It makes all kinds of implications, insinuations and just incorrect statements concerning your system in comparison to other heating systems. Most of the time you're really spinning the numbers and making crazy assumptions behind the scenes.
Nearly half of all residential water heaters in the USA are conventional electric tank systems. Less than 1% (using any metric other than total installation cost per GPM) are electric tankless systems because they just suck in every way.
Lets limit comparisons to other electric systems. There are really only two. The cheap (traditional tanks) and the best (heat pumps).First, efficiency....
Even the cheap conventional water heaters are >90% efficient! Go online, find a cheap water heater, look at the mfr specs and how they measure efficiency.
"The largest drawback of tank water heaters is that they waste a tremendous amount of energy heating water when no one is using hot water."
nope.THAT 90% EFFICIENCY NUMBER INCLUDES ANY HEAT LOST WHILE SITTING THERE OVER 24HOURS!eCFR Code of Federal Regulations...
10 CFR 430, Subpart B, Appendix E..
"Uniform Test Method for Measuring the Energy Consumption of Water Heaters"
"24-Hour Simulated Use Test"
Conventional electric storage water heaters have improved REAL WORLD efficiency results thanks to this extended testing period. It forced manufacturers to add internal liners, outer coatings, better R-value bulk insulation, eliminate drafty outer shells, isolated the base, use two heating elements and put thermal taps on the ports.
Heat pumps produce just as much hot water, but consume a half (real world typical) as much power. No violation of thermo.
How does Heatwork's tankless 99% efficient unit provide "up to 40% energy savings" unless it's compared to...something else? All cost saving comparisons I find on the KS page were referencing gas heater numbers or in the case of that EnergyStar pamphlet, specs from systems that haven't existed for half a century....Operational cost savings...
Cost comparison with a traditional tank is easy (90% vs 99%). A typical family would therefore see an average annual savings less than $50
ROI = 'div by zero'
Comparing to the operational cost of a heatpump is also easy. The Heatworks unit consumes, on average, twice as much power. Space and Installation costs...
Tankless systems either take up your storage areas or they require holes punched in your walls, pipes and two phase lines run to those walls and access panels installed.
"you will save space with our small 12" long unit rather than a big 46" unit!"
With plumbing, junction boxes capable of handling 10AWG wire and access panels, how much space does this 12" thing take up? How many of these small 12" units will I need to install to replace one $300 conventional tank? I might need more rooms in my house.
You say in your video that:
"in new construction, it's actually less expensive, up-front, to install these around the house, ... and run cold water and electrical wiring to them, than it is to run hot water pipe through the house."
I'm waiting for the disclaimer on this one. Considering your product's capacity is so low that it needs to be used in conjunction with a conventional hot water tank.....a tank that gets water to your product with hot water lines.... Capacity...
I have two 7GPM showers and four 2GPM sinks. My water comes from the utility at 55F and I want it 120F. So each of my showers would need 66KW (7 of these units), and my sinks would each need 19KW (two units). My entire home service is only rated at 44KW and I need to supply 210KW!? Assuming I dedicate an entirely new electrical service to these things, and only let one turn on at a time... I can just barely take a comfortable shower?Water savings......
The "10% water savings" statement assumes that 10% of my TOTAL water consumption is allowed to flow down the drain, right? A large amount of the water I use is 100% cold water. Dishwaster, cooking, drinking, toilets. These things don't let the water run while waiting for the warm stuff. To offset this fact, I would need to increase the relative percentage of time I waste water while waiting. So how do you calculate the average amount of hot water that goes down the drain?!
In your video you say that this unit saves one to two GPM
every time you use your hot water tap. What does that even mean? It restricts my flow by 1.5GPM? Couldn't I do the same with an obstruction like a hunk of dirt? Then you state it saves 20 to 40 gallons per day without explaining how that is even possible.The alternatives...
Heat pumps are better solution to any hot water system in every way. They consume (typically) half the power as even this 99% efficient system for the same heat output as a conventional tank (no violation of thermo laws). They are able to service an entire REAL WORLD home, not a home that only turns on one super low flow faucet on at a time. Upfront costs of heat pumps are the only down side. Although more expensive than conventional $300 tanks, they have a measurable ROI over something like this.
This device might have applications, but I don't see them. Anyone that wants the luxury of instant hot water just needs to install a circulating bleed valve. It's a very cheap DIY project that bleeds a very small amount of hot water from the far end of the house to mix with the cold supply periodically. This keeps the hot water supply line warm without wasting much energy. Simple and cheap.