Are EPA numbers complete BS?

[iamlucky13]

I would love to agree with you but that is wrong. I had a car rated at around 35 MPG that actually gave me a fairly consistent 45 MPG, it was a little car. I now drive a car rated at 38 MPG and am lucky to ever reach that number. Both were 5 speeds and the same manufacturer. I drive my present car about the same as that earlier one. Same driver, same driving habits, same everything except the car. The cars are not at all like the ratings would suggest. The one with a better mileage rating is doing worse than the other. I owned both cars for over 5 years so it was not a case of first year or anything like that.

That's disappointing to hear. I've never been unable to beat the rating, although with our newer model Outback, the city mileage rating is hard to hit in the winter.

It's not a Hyundai or Kia, per chance, is it? Both of those companies got caught lying on their mileage ratings last year. With the number of cars on the market, the EPA does not test all of them. They give the manufacturer the test procedure, and enforce it by randomly selecting a number of vehicles to test themselves each year, in addition to testing vehicles that receive unusually large numbers of mileage complaints (pretty much all of them receive some complaints).

They're not the only ones to cheat their ratings, but as far as I know, they took it the furthest.

And the old car wasn't a Metro, was it? It was rated for 35 mpg, but everyone I knew who owned one got at least 45 mpg.

 

[Quentin2]

I need a life, found this digging around. Hope he doesn't mind but this is a 3 year old post from bkvp.


As far as heat output, boy marketing guys are good! Fact, the EPA says there are 8,600 Btu's in a pound of hardwood fuel. Regardless of whether it is 8,600 or 9,000, just remember it is limited. So when you are shopping for a new stove, just look at the total amount of weight in pounds the stove can hold with fuel at 20% moisture content ( a nice round average although not ideal). If a stove will hold 50 lbs. of wood at 20%, then it has a maximum total Btu production of 430,000 Btu's from that load. As manufacturers we can't fudge that number.

Then locate a brochure for the stove from prior to 2008 (when the Fed. Tax Credit allowed nearly every stove to be eligible for the tax credit) and get the HHV (high heat value) efficiency for the stoves. Most were around 78% on the brochures for the LHV, so just subtract 10-11% and you'll get the HHV value.

Back to the example above, so the stove has 430,000 Btu's in the load and has a HHV (real world) efficiency of 68%. That leaves 292,400 Btu's to actually heat your home. Divide that by burn time and you can easily get the average heat output of the stove. If a stove has a low burn time of 10 hours, that 29,240 Btu's per hour in your home. If the high burn times is 5 hours, you get 58,480 Btus's AVERAGE into your home.

All the rest is marketing.

 

[tarzan]

Quentin, thank you (and BKVP) for that post.

That's a great formula for estimating BTU's but in order to use it accuratly you probably already have the stove in your living room

Not trying to take anything away from your post but for me the gripe about BTU estimates isn't as much about the stoves we have running in our homes as it is about the stoves setting in the stores.

There are many folks who base there stove buying decisions heavily or solely on the BTU's it is capable of, and why not? I know I've had several propane and kerosene heaters for things like camping and all I need to figure out what the heater is capable of is look at the BTU's stated on the box.

Not so with wood stoves. Anybody reading this thread will get at least three different versions of how the EPA gets there numbers and at least one says they are mostly default numbers because if a company wants the real numbers they would have to shell out thousands of dollars for them! Why would they do that when it seems like the mfg can basicly make up there own exaggerated number for there glossy literature if they so wish.

It wouldn't be very hard to come up with a realistic output number or at the least QUIT throwing around the unrealistic numbers without an "*" beside them.

*This stove wasn't really tested!

*The BTU rating for this stove was attained by over firing it to the point it was then sent off for scrap!