Modern, efficient, EC motor range hood?
When I set out to get a range hood recently, I assumed there’d be modern, efficient options, including EC motors with variable speed and LED lighting. But after scouring literature and examining some showrooms, I have not found any, although most hood literature doesn’t actually say what’s inside, so I can’t tell. But of the ones I’ve seen up close in showrooms, even the very high-end models all have standard AC blowers, and every “variable speed” unit I’ve seen is just a $15 PWM controller on a standard AC motor. Almost every hood still has halogen bulbs. I’ve not found any with linear LED.
So I decided I’d just make one. But to my surprise, EC blowers are not as readily available as I assumed they’d be. For example, a typical old-style AC hood blower is the ~400 Watt EBM Pabst D2e146 like this:
https://www.mouser.com/datasheet/2/120/embpapst_07122019_D2E146HT6594_KM85813_-1622418.pdf
But EBM has an identical blower with a modern EC motor that is more than 2x more efficient, and has true variable speed control, their D3G146:
However, although they’ve made this blower for a decade, it’s not in the distribution channel, because it’s not a popular component (ie, EBM only makes in on-demand for sufficiently large OEM orders)
However, the 220v version of this blower is widely stocked by European distributors. Presumably this is because Europe is ahead of US efficiency-standard-wide?
So does anyone know of a modern high-efficiency range hood brand/model? Am I just not looking in the right place, or is this market truly so far behind the curve that every hood sold in the US today is still 1950’s tech?
Btw, and no surprise here, but every appliance purveyor I’ve talked to just has blank stares when I ask about this. I’ve even talked to a couple hood manufacturer reps who have no clue what an EC motor is.
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Ducting design/size, capture area, and appropriate fan capacity SHOULD be your concern. If you pay attention to these items than the EE of the motor itself becomes irrelevant.
Forest before the trees my friend...
The EE of the motor is irrelevant? The two fans I cited have identical capacity (fan curves), but one is twice as efficient. Pretty ironic on this forum to be told that's irrelevant.
So how much $$ do you think one would save on 15 minutes of run time 3x-4x a week?
You should really run your range hood every time you cook. We cook 10-15 times per week with the fan running 15-30 minutes, sometimes an hour. Say four hours per week, or 200 hours per year. If the fan is using 400 watts, that's 80 kWh/yr. At our delivered electricity cost of 16.3 cents, that's $13 per year. If an ECM motor cuts that in half, obviously we'd save $6.50 per year. If the upgrade to ECM costs $130, that's a 5% return on investment. Not bad when it's a sure thing. But not enough savings to really worry about too much. If you were running a restaurant, that would be a much different story. Imagine the savings of cutting commercial exhaust hood energy use in half!
Thank you for the cost calcs.
Watch out for the use of ROI. The ROI, technically is not positive in your example until year 20 (not accounting for inflation, opportunity cost etc). $130/$6.50 per year = 20 years.
You're conflating ROI with breakeven or payback. The ROI, positive or negative, starts the moment you spend the money. I should have mentioned that my values were for simple return, not compounded return.
If it is a good idea show us the math. What is the return on investment?
You say the conventional motor uses 400 watts but not what the ECM uses.
What is the price difference?
At .11 a kWh how many hours will you need to run the fan to break even?
How many hours a day do you run your vent?
I would be surprised mine hood runs one hour a year.
Walta
Pretty hard to price compare if you can't find one for sale.
Assuming someone doesn't live off restaurant and take out food, a typical range hood will run at least 300 hours a year. If you run yours less than 1 hour a year, then I don't know why you'd waste the money on installing it in the first place.
Aren't EC motors also quieter? Maybe it's just coincidence that the two EC motor appliances are many dB quieter than any other motored appliance I've ever owned or heard.
To answer the ROI questions, I run range hood at least an hour a day (typical for anyone who actually cooks regularly, as Trevor noted) At an average speed, the EC motor uses ~150 Watts less than the AC motor. At my electricity rates that's $15/year.
But the EC version of the blower is actually less expensive than the AC version, so the ROI is negative -- even the guy who runs his hood one hour per year would save money with the EC.
I talked to manufacturer and I learned that the 115V EC blower is only manufactured on demand because there's no U.S. market it -- low ROI due to cheap/subsidized electricity, retrograde attitudes, etc. However, the 220V EC version is a standard item in Europe, where electricity rates and regulations make the higher efficiency attractive.
My goal wasn't financial ROI. It's partly that it just feels wrong to be installing 1950's technology in 2020, and partly because EC motors are quieter and have better speed regulation. I also just resent paying top dollar for a "premium" product (Wolf, etc) that is really just low-end commodity stuff mechanically.
EU is very much regulatory driven because frankly that's their purpose. In any case clearly $15/yr isn't going to be a deal breaker for the environment or you financially. It's what I'd categorize has high-level fruit. Akin to fretting over being unable to reduce the ACH of a house from less than 2 to less than 1.
Now obviously if the existing design is severely compromised (blower mounted at the hood rather than exterior termination or farther way via inline, narrow duct, lots of bends, narrow capture area) which would require significantly longer run times at high speeds, then maybe it might be worth the trouble just because the EC is quieter.
John, I agree that this is high-level fruit, but I'm not sure your ACH analogy is a good one. On a recent energy model to a 3000sf house built to PGH standards (other than size), going from 3.0 ACH50 to 1.0 ACH50 would save $165/yr, and that's with a very efficient heating system. I estimated the cost to go from 3.0 to 1.0 at $400 (some time, tape and sealant). I'll take a 40% ROI any day. (I know you said 2.0 ACH50 but I didn't model that.)
Going from 1.0 ACH50 to 0.6 ACH50, on the other hand, only saves $22/yr. If that also costs $400, which is optimistic, the ROI is only 5%.
The main benefit of EC fans is in speed modulated applications like furnace air handlers and the like. In fixed-speed applications like a typical on/off type of range hood, there is less benefit. That's not to say there is NO benefit in fixed-speed applications, just that in fixed-speed applications there is much less to be gained. Note also that you can't do a "volts x amps = watts" with regular motors due to power factor. Typical AC motor power factor will be 0.8 or less in most cases, which means that the simple equation will overstate the actual energy consumption of the motor.
There are range hoods out there with LED lights, I just recently installed two of them myself. I like the LEDs since there are no bulbs to change, in addition to the better efficiency. The cost premium for the LEDs was pretty minimal too, maybe $20 or so if that. It's hard to split the cost out since the LED model also has a dual blower for more airflow.
If you want to run a european blower in north america, you can use a simple step-up transformer to get the 220-230v AC that the european equipment usually needs. The controller for an EC fan is likely to be OK with 50-60Hz, so the frequency difference isn't an issue.
Electricity in the US is not "subsidized". Europe tends to tax everything much more, and many of those countries don't have local energy supplies so they are importing everything from somewhere else often resulting in higher costs. There may be a quicker ROI on a fancy blower over there, but overall you're getting a lot less for your money.
Bill
If you really want an EC fan, you can go with an inline fan and hood liner: https://www.hvacquick.com/products/residential/Kitchen-Exhaust/Kitchen-Exhaust-Fans/Fantech-FG-EC-Series-EC-Motor-Inline-Centrifugal-Fans
Fantech makes and sells an EC inline fan appropriate for building quiet range hoods (and other ventilation etc). https://shop.fantech.net/en-US/fg--8--ec--centrif--inline--fan/p106713
A few thoughts.
Some decent info on range hoods here: https://www.gardenweb.com/discussions/5161173/hood-faq
I believe Accurex blowers are available with EC motors (https://www.accurex.com/products/exhaust-fans/inline/xid). Fantech was looking at EC at one time but I believe they determined that they were not cost effective for anything below about 2500 CFM or something like that.
I agree with paying close attention to duct design and overall static pressure. That is likely to reduce your energy consumption by a lot more than just using an EC motor.
I think every range hood I've seen is at least multi-speed if not variable speed so wouldn't an EC be of benefit? Of course the payback might be measured in decades.
I think the LED issue is one of heat and inability to cool an LED lamp in a place with quite high temps. This is also a problem in some downlight fixtures that get too hot for many LED's. You could always try simply using LED lamps but I'd guess they won't last long.
Interested to see what all you come up with.
It is likely that heating or cooling the makeup air from depressurizatiin of the envelope will cost much more than the cost for running the range hood motor. To put this in perspective, a typical 250 cfm hood will evacuate 15000 cubic feet of air in an hour. That air comes from the outside, in a heating dominate climate like mine (average yearly winter temp o C.) evacuating 15000 cubic feet every day for 8 months would add about 600 kWh to my yearly heat bill. Running the fan is just a fraction of cost of heating and cooling the make up air.
I'm kind of puzzled by the comments about LED lights being hard to find in range hoods. I got LEDs in the range hood I bought two years ago, and it took no effort at all. I had the choice of dozens of models with that option, just from a single seller.
There are lots of EC inline fans, but my application isn't suited to inline.
David, good point about makeup air costs dwarfing blower efficiency in cold climates, though not the case in my temperate climate.
Zephyr7, I've never even seen a range hood that was just on/off -- every hood I've looked at is 3 or 4 speed or variable speed. But I'm only looking at high-end, large (~1000 cfm) hoods. Probably many small ones are single speed. But the variable speed ones are just PWM dials on AC blowers, so not great -- the can't modulate the low end, and they usually make an annoying humming. I think the superior variable speed of an EC motor will be a real value to some. For example, I often make a large pot of stock that'll simmer for 8-12 hours. Having a very low fan setting over this would be nice.
Re: subsidized electricity, I should have said "more subsidized" in US. Almost all countries substantially subsidize all forms of energy, in a zillion different ways, not the least of which are: tax policies favoring a particular energy sector; insulating energy producers from economic "externalities" (eg, pollution and health costs); military investments (political stability for energy extraction was one of the goals for the ~10 trillion dollars spent in the middle east over the last three decades)....
Trevor, most of the fancy hoods seem to still have halogen PAR30, or just LED Par30. But few seem to have thoughtfully integrated LED. In my prototype hood I've got a linear LED at the front edge, which is much nicer than the halogen floods in my $3000 "high end" range hood. The linear lamp has much better diffusion and fewer shadows, and it only tales up 1" of leading edge of the capture area, unlike the typical hood which sacrifices 3-4" of the capture area for the light bar.
https://www.johnsonelectric.com/en/solutions-by-industry/for-industry-segments/home-technologies/range-hoods
https://mag.ebmpapst.com/en/industries/household-appliances/cooking-the-eco-way_7959/
Thanks!