Combined heat and power plant to achieve the KFW efficiency house?

Hello,

does anyone have experience with combined heat and power plants and the subsidies? We are considering a major renovation of a multi-family house with 5 units, and a combined heat and power plant would of course be relatively appealing, even if I, as a landlord, cannot benefit from the efficient heating but at most from the electricity sold to the tenants.

In our private house, a heat pump helps us achieve the KFW standard (85 or even 70) - unfortunately, I have not been able to find out how this looks with a combined heat and power plant. If not, then a large-scale renovation is hardly worthwhile and a moderate one would be more appropriate. Then each apartment would, for example, "only" receive a modern condensing gas boiler and the double-glazed windows could still serve their purpose for a few more years.

Thank you very much

Is it even possible/allowed to sell electricity generated in this way to tenants???

At least with photovoltaics, I am quite sure that it is not that simple.

Of course, you are allowed to sell generated electricity to your tenants, but for that you need a supply license.

Go to the customs website, there you will find the necessary information under the menu item Private individuals -> Electricity in the household. Alternatively, you can call your responsible main customs office.

However, you should calculate whether it is worthwhile. Excess electricity can also be fed into the grid. But if the combined heat and power plant is only there to achieve the values on paper, it sounds more like expensive but effectively useless.

A colleague owns a condominium. To achieve the KfW 70 standard in this building, a combined heat and power plant was also installed, but not the necessary installations to distribute the electricity to the apartments. Meanwhile, the thing stands quietly in the basement, the heating runs on the also existing gas boiler.

Yes, that sounds like a bit of a scam, doesn’t it? :D Since 2016, built-in combined heat and power plants have been remunerated with a flat rate of 8 cents/kWh for fed-in electricity – and the grid operator is obliged to do so. Self-consumed electricity is still subsidized with 4 cents/kWh. I have already found that out. Additionally, it seems possible to get a refund of the energy tax on the raw material natural gas over the depreciation period (0.55 cents/kWh gas as far as I know).

In our case, of course, it is advantageous to reach the Standard 70, but the electricity would have to be fed in 100% since we live in a neighboring village. On the websites I have visited so far, it always said it was a win-win situation because you are always cheaper than the local supplier and thus receive the electricity price plus 4 cents. I would of course research that more thoroughly – thanks for the customs tip.

It is only important to know exactly how the efficiency of a combined heat and power plant is evaluated by the KFW. With top insulation and new windows, etc., but with normal gas heating, I only get just under 100 kWh/m²*a with the BMWi renovation calculator and thus no efficiency house standard. A heat pump (air/air) scores 45 kWh/m²*a. Unfortunately, combined heat and power plants are not selectable... The calculator is very rough anyway.

Maybe a KFW advisor has to calculate that for me, but that just costs again :)

I recently called Senertec about the "Dachs." They said they have expert reports for it, and a combined heat and power plant would be possible!

Sounds interesting at first, but it is really a lot of work.

Annual financial statements
Tax returns
Reimbursement applications
Invoicing

... and then it can always happen that your tax office considers the rental of extensive own properties with power generation as business assets - then the tax exemption on disposal would be gone ...

That's too much complexity for me!

Yes, it seems like quite an effort, but selling your own electricity and possibly operating a small photovoltaic system in combination to act almost 100% self-sufficient sounds appealing. Even if one still depends on gas (biogas?).

They take over the measurement (the current amendment provides that one may no longer do this oneself) as well as the billing with the buyers etc. Once a year then only a reimbursement application for the energy tax. I am still convinced of it.

Unfortunately, KfW has suspended the direct funding option for a CHP since 31.3.16 :-( So it only helps in achieving the standard and the bill can no longer be discounted.

How it will be with the tax office – there are also scary stories about that. Next research topic anyone has experience?