Uh, dude, "NEW" ???
That hit-job on tankless heaters is
over a year old now!
And it's barely worth the toilet-paper it's smeared on, IMHO. Because...
A: They don't state the financial assumptions about fuel pricing or the cost of money- no hint at all about how (or if) they calculated a net-present-value on the cost delta.
B: They overstate hot water usage (which improves the picture for tanks, but is fairly neutral for tankless) at ~20% above the national average for a family of 4 (on which the DOE's EF test was designed)
C: They doped the water to exaggerate liming/scaling effects on a tankless HX. (Hard-water areas really DO need to be mindful, but mine went 15+ years without even a hint of scale issues or any other maintenance on city water in New England, retiring it fully-working when I installed a new heating system that included a buffer tank with an internal HX for the DHW.) It's a useful warning, but irrelevant for the majority of users.
D: They don't address the REAL reasons most peops opt for 'em: Filling huge spas &/or very high volume HW use and space-savings.
E: They don't name the "outside lab", nor do they give any of the raw data and only the vaguest sketchiest description of test methodology, never mentioning size of individual draws (which can degrade the efficiency of a tankless dramatically at the low end) or any other factors other than daily volumes (
volumes that are ~20% over the national average for a family of 4., as previously noted.)
This is a hit-job, not a well reasoned analysis. It's designed to overstate the real-world efficiency of a tank, and exaggerate the maintenance issues of a tankless.
Take the efficiency information from people who actually measure stuff without an agenda, and under varying circumstances to determine true average efficiencies for different patterns of use:
http://www.aceee.org/conf/08whforum/presentations/1a_davis.pdf
(Note the above isn't a "rah-rah tankless" piece by any means- a 92% steady-state thermal efficiency condensing tankless only hits ~75% average efficiency in one of the use profiles. Read & ponder. There's a heluva lot more
real comparative info there than the CU piece.)
The financials you'll have to do on your own-
fuel prices vary by as much as 600% BTU-for-BTU between low-price natural gas markets vs. high price propane markets, and it makes a HUGE difference on if & where the net-present-value boundaries go positive. The one-size-fits-all financial analysis conclusions of the CU piece is utter CRAP!
Will the "average" family even make it back on fuel savings? Depends a lot on the the price of NG over the next decade, (and I'm guessin' not), but fuel savings is about the 4th or 5th reason on the prioritized list of why most people who go tankless make their decisions, behind arbitrarily high draw volume (not to be confused with high flow) & space savings (the two most cited, in my limited experience), and appliance longevity (a distant 3rd.)
They also don't compare some of the better low-end cheap to install versions that are ~80% efficient (eg: Bosch 1600H), which still beat tanks soundly on average efficiency, but are nowhere near as complex or expensive to install as Noritiz & Takagis. (Atmospheric draft therefore B-venting OK, ignition powered by water flow so it needs no electricity, etc.) NPV on those looks pretty good for most propane users, if you can tolerate the 30-117KBTU modulation range. It's good enough for a single-shower even in cold-water country, maybe two in FL or SoCal but it's HX is fairly high-head, not designed for super high flow on the water side. It's about right for weekend cabins & condos, etc.- VERY low maintenance.)
BTW: Don't confuse me for a huge tankless fan- I fully understand their merits & limitations (I think they make better modulating combi space-heating/DHW boilers than water heaters, even if they're more efficient than tanks.). Still, I've yet to meet anyone who has lived with one for awhile who is dying to go back to a tank. But that consumer-reports piece is a downright
LOUSY bit of analysis, and gives the reader no tools or information by which to analyze whether it makes sense for
them, and how
they use hot water.