# On the Economics of the Domestic E-Cat

The following is a guest post submitted to E-Cat World by Piero Ferreri, an engineer from Milan, Italy. I am always happy to include posts written by ECW readers. Please feel free to send me anything you would like to be considered for publication here.

While my background is technical, I like to verify that any technical proposition makes good financial sense. So I started asking myself how convenient an E-CAT would be to heat a house, as compared to a normal oil based (or gas based) heating plant.

So the first question was: how much heat do I need, for an average house of say 150 square meters (about 1,500 square feet). The number would very much depend on the quality of the thermal insulation, and on how cold it is outside. Well, I had no clue.

The other day, though, I was in my house in the mountains, which is about that size, and I happened to look at the specs of the burner we have there: it said: thermal output power: 45 KW. Aha! I had a number. This means that 5 home E-CATs of 10 KW each would do the job. Sounded like a lot, but now I could do the math: let say I keep them running in the cold season only (6 months – and forget summer conditioning for a moment). I only need one charge per unit every year. At 50 bucks per charge (Rossi’s words) that means only 250\$ per year. Now let’s be fair and add the depreciation of the units: Rossi said a unit should cost less than 1,000 \$ and would last 30 years. Add another 2-3,000 \$ for the installation + control unit, etc.(?), all in all this only adds about another 250 \$ / year of depreciation. Fabulous: 500 \$ / year to heat my house in the mountains for an entire winter would be a real bargain!

But wait, I forgot the electricity needed to keep the stuff running!

Let’s see, we have a COP of 6. This means that, on average, we need to spend 1 KWh of electricity to generate 6 KWh of thermal energy. So, my 5 units, with an output power of 50 KW thermal, need 8.33 KW of electric power running for 6 months (which is 4,320 hours). This means 36,000 KWh of electricity. Omygosh! In Italy, where I live, 1 KWh cost about 40 Cents (let’s say \$ cents, for the sake of simplicity), and the calculations tell me that I need to spend another 14,400 \$ in electricity bills every year. Good grief! Is this “cheap energy for the masses”?

Something had to be wrong. I decided to take the problem from another angle: I know that to keep that house warm in winter we burn about 20 liters of “gasolio” (heating oil) per day. How much energy is that? Some surfing in the web told me that 1 liter of oil generates 8,500 KCalories, and that 1 Kcal = 0.001163 KWh. So, the result is that my 20 liters of oil per day correspond to 198 KWh per day, which means, lo-and-behold, I only need 8.2 KW of thermal power!

Now, may be many people knew this already, but for me it was a surprise. 1 home E-CAT of 10 KW is all we need to heat an average apartment. Evidently my current burner is oversized for the need, or probably the 45KW is the peak power it can handle, and not what I normally use. Whatever. In any case this is good news. Now the calculations tell me that my total cost is 50 \$ for one charge, plus 100 \$ of depreciation and, uhmmm, still about 2,900 \$ of electricity bill (at Italian rates).

Let’s compare it with what I would spend today: if I use my 20 liters / day for 6 months, the heating bill, at 1.5 \$ / liter (yes, Italian price), would be around 4,500 \$, so an E-CAT would still represent a 33 % saving. But is it really so great? Ater all, if I could just switch from oil to gas, which costs about 30% less than oil, the benefit would simply disappear.

I know that in the US and other countries the cost of electricity is much less than in Europe, so may be the electricity bill would be, what, 1,500 \$? Yet, shall I conclude that there would be some saving only where the electricity is cheaper? This sounds almost like a contradiction. Uhmmmm…

It looks like either we have an E-CAT with a MUCH higher COP, reducing dramatically the amount of electricity needed to sustain the reaction, or we must replace the electricity with a different, much cheaper, source of energy.

For example, running the above scenario with the same numbers, but replacing the electricity with heating oil, the calculations tell me that I would need around 4 liter of oil per day to keep the E-CAT running, and, at the current cost of about 1.5 \$ per liter, the input energy would cost around 870 \$ per winter, a much more competitive proposition (No wonder Rossi has been doing research on oil-driven E-CATs).

I think it would be interesting to know what other followers of this site think of all these considerations, and if they find some fundamental flaw in my assumptions.

Piero Ferreri

• Simone

and what happens if you consider giving the electrical input needed for the E-CAT with a home solar plant? 😀

• Redford

“Omygosh! In Italy, where I live, 1 KWh cost about 40 Cents”

In France, it’s around 10 Cents. Nuclear Plant For The Win.

• Redford

I checked and according to this document, you pay way too high.

Italian while one of the most expensive, charges typically 20c per kWh.
http://www.developpement-durable.gouv.fr/IMG/pdf/LPS36.pdf‎

It’s the highest with Danemark. Lowest is Bulgaria with 7,8.
Average europe is 15,8 for electricity, 6.52 for gaz. With a cop of 6, it means eCat heat is 2.6 vs 6.52 for gaz. Note that it’s not insanely low – gaz probably was lower than that decades ago. Still, pretty attractive. Also wait to see Hot Cat made-kWh of electricity price rate =)

• Redford

Wow, actually those are 2009 figures. Gas skyrocketed since.
Latest available charts are for… 2010, and gas already had climbed at 7.1
http://www.developpement-durable.gouv.fr/IMG/pdf/CS249.pdf‎
If your country makes its electricity out of fossile, both will always be correlated, so I guess it doesn’t matter a lot. eCat is interesting in any case, and gaz cat even more.
If your country use anything else, eCat is even more interesting.

Gaz prices will probably rise until eCat becomes a massmarket anyway =)

• Piero

The price in italy is actually a funtion of the peak power you ask for. For 3 kw it’s as low as 17c /kwh but for 10 kw it goes up to 40c / kwh