I don't think that is actually true--the marginal efficiency is about
the same for a tank and tankless, assuming comparable combustion
technology (i.e. both 80% non-condensing). The tankless wins by
eliminating the fixed standby costs which are basically independent of
usage. So you could rephrase your statement as "with a tankless
someone could choose to spend some of their savings on a longer
shower, and still come out ahead, if it isn't too much longer."
So, you don't compute standby loss dollars in your scenario... Any
other actual dollars spent that don't count in your theoretical
calculations? Maybe you should rewrite what you wrote. I stand by
what I wrote and, judging from your editing, I'm also a better
No, it's not that the standby losses don't count, it's that they don't
depend on usage. I guess I read your original statement as being one
about incremental usage costs, in which case they don't appear. But
apparently you were referring to average usage costs, where they do.
P.S. Analytically, what I'm saying is that a tankless will cost R * U
dollars/month, where U is the usage in gallons/month and R is a rate
in $/gallon. While the tank will cost you S + R * U, for the same
rate R, where S is the dollar cost per month of the standby losses.
Startup time for hot water is dominated by the piping length between
the heater and the point of use. The tankless adds at most 2 seconds
to the startup time. For a 2.5 gpm shower, that's less that 0.1
gallons. A small effect.
Really a full minute, not on mine, mine fires in 2 seconds after water
is turned on, probably another 3-5 seconds to fully heat output. I say
you are unqualified to respond to tankless. I dont realy notice a
difference from the changeover, Pipe length from heater to faucet is
the issue. Your Full Minute statement is untrue, the issue is cold
water in the pipes already. Im now at a tank location, about 40
seconds I need to get HW out of 50 ft of pipe. The tankless location
with about 15 ft is maybe 10 seconds 10 or so to push out cold water.
my my tank vs tankless is now hotter than K&T and insurance
lets have a group hug, no groping!!!!
so all those concerned with standby losses do you turn your vehicle
off at long lights?
one day every new home will be required by law to be superinsulated,
which could drop heating costs to near nothing
On Sun, 13 Apr 2008 14:33:37 -0700 (PDT), " email@example.com"
That day better come soon. I'm told Alberta's natural gas production
is 12 billion cubic feet per day and 1 billion of that is currently
used by the province's tar sands operation. The NEB is forecasting
production to fall to 9 BCFD by 2012, at a time when 6 BCFD -- a full
two-thirds -- will be used by the tar sands, in large part to power
the new SAGD (Steam Assisted Gravity Drainage) plants now under
construction. That suggests our natural gas supplies for domestic use
(and export to the United States) will fall from 11 BCFD today to as
little as 3 BCFD in less than five years.
Cold showers for everyone!
Ya, really. I get a great big laugh everytime i hear someone say "gas will
be $4 a gallon by the end of summer". YA YA, you been telling me that for
7 years now. Some day they will be right... LMMFAO!!
Well, for those living in San Francisco the wait won't be long.
According to the AAA, the average cost of regular unleaded is $3.929,
up from $3.758 a month ago; mid grade and premium are selling at
$4.181 and $4.249 respectively and diesel is $4.422.
The wait is already over in Hawaii where regular gas in Wailuku sells
for $4.072. But since Hawaii is not part of the United States, it
doesn't count, right?
I'm sure the citizens of CA and HI will be amused to hear that.
Be that as it may, the AAA national average for regular unleaded is
now $3.386; mid-grade and premium are $3.596 and $3.725 respectively.
Diesel is selling for $4.119.
Crude oil is currently trading in excess of $113.50 a barrel and if
the EIA's inventory numbers fall again tomorrow we can expect more
turmoil in the oil markets. Refiners are not in the business to lose
money, so either wholesale gasoline prices will rise or they'll simply
cut back on production -- either way, retail prices will increase to
reflect the higher cost of this more expensive crude.
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