For those who have done the math, I'm curious about something.. not about the device itself.. but the bigger picture. If the number 45kW is roughly correct (amount of power needed to heat 4 gallons/minute on-demand from 20C to 60C), then there is an implication here.
If the device runs twice a day for 20 minutes, that's 30kWh worth. Household average electricity usage is 8000kWh/year, or about 22kWh per day. So if I use one of these devices, I'm going to more than double my daily electricity consumption (assuming I heat water with gas today).
According to this paper: http://www.toolbase.org/PDF/CaseStudies/ResElectricalEnergyUseData.pdf peak household electrical load is about 5x average load, which is roughly 1kW. So peak is 5kW at any one time. A wanderport shower will draw 45kW, or almost 10x a normal peak, and 50x average draw.
So for every 1% of the population that uses this device would cause a corresponding rise in grid load of 10% (assuming they all jump in the shower at the same time).
So while as a shareholder I'd love to see 3% of the population having a Wanderport water heater, our electrical grid wouldn't be as happy (again, assuming everyone showers at the same time).
Even at 100% efficiency, "on-demand" heating of water is a huge instantaneous energy draw, whereas with storage the power is consumed much more slowly over time (which is why I only get cold water after my wife and kids are finally done).
Just some thoughts to trigger some discussion. Clearly the need for smart-grid is there: distributed supply, more off-peak demand, intelligent and efficient power storage, etc.
Anyone know of any good smart-grid related investments? ;-)
Tykun
P.S. Sorry if I'm way off on the math. This was a quick back-of-the-napkin analysis. This post is more of a whimsical musing, and not an attempt to validate or invalidate Wanderport's claims.
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