Is a catalyitic stove really more efficient since a cat looses its efficiency with age

[Fargo]

So as I am constantly thinking about wood stoves since my purchase, I am questioning the efficiency of catalytic stoves. I will preface by saying a lot of my research was done by chatgpt. So it could be completely wrong. But I have found that a cat can loose 10%-15% efficiency per year. I have also found that a stove with no cat or secondary burn may only be around 40%-50% efficient. So a stove like the BK Ashford 30.2 may start off at 83% efficient, but the stove itself might (my assumption) only be 50% efficient and the cat might be doing the other 33% of the work. If that is all true and the cat is loosing 10% efficiency over a 5 year period, a cat stove is only averaging 75.4% efficiency over that 5 year period. Or about the same as a clean non-cat like the Alderlea T6 (74%). (The 2 stoves I was considering). If my data is correct, it would seem to me, a cat should be replaced at a minimum of every 5 years to maintain efficiency.

What am I missing? If a cat looses 10% efficiency per year how is it more efficient than a non-cat, which as I understand does not suffer this type of loss. The break down looks something like this.

Given
Base stove efficiency = 50%
Catalyst adds = 33% when new
Total when new = 83%
Catalyst degrades 10% per year (multiplicative decay)

Summary: Efficiency Over 5 Years
Year Catalytic Efficiency Total Efficiency
0 33% 83%
1 29.7% 79.7%
2 26.73% 76.73%
3 24.06% 74.06%
4 21.65% 71.65%
5 19.49% 69.49%

Final Answers
Efficiency after 5 years: 69.5%
Average efficiency over the 5-year period: ≈75.4%

 

[EbS-P]

So as I am constantly thinking about wood stoves since my purchase, I am questioning the efficiency of catalytic stoves. I will preface by saying a lot of my research was done by chatgpt. So it could be completely wrong. But I have found that a cat can loose 10%-15% efficiency per year. I have also found that a stove with no cat or secondary burn may only be around 40%-50% efficient. So a stove like the BK Ashford 30.2 may start off at 83% efficient, but the stove itself might (my assumption) only be 50% efficient and the cat might be doing the other 33% of the work. If that is all true and the cat is loosing 10% efficiency over a 5 year period, a cat stove is only averaging 75.4% efficiency over that 5 year period. Or about the same as a clean non-cat like the Alderlea T6 (74%). (The 2 stoves I was considering). If my data is correct, it would seem to me, a cat should be replaced at a minimum of every 5 years to maintain efficiency.

What am I missing? If a cat looses 10% efficiency per year how is it more efficient than a non-cat, which as I understand does not suffer this type of loss. The break down looks something like this.

Given
Base stove efficiency = 50%
Catalyst adds = 33% when new
Total when new = 83%
Catalyst degrades 10% per year (multiplicative decay)

Summary: Efficiency Over 5 Years
Year Catalytic Efficiency Total Efficiency
0 33% 83%
1 29.7% 79.7%
2 26.73% 76.73%
3 24.06% 74.06%
4 21.65% 71.65%
5 19.49% 69.49%

Final Answers
Efficiency after 5 years: 69.5%
Average efficiency over the 5-year period: ≈75.4%

Life of the cat is roughly 10k hours. Do in a decade or 3 years. It doesn’t change the efficiency. The cat stoves are more efficient at lower operating temps. Burn less wood but you get replace a cat every 10k hours. They work well for some who don’t need lots of heat. Once you need to go to a 6-8 hour burn cycle the efficiency difference is less compared to a secondary burn stove.

The cat efficiency is just being measured how? Probably not the same way we measure stove efficiency.