ᐅ Home Construction 2016 + Gas Heating

Unfortunately, I have the standard ones – they might be sturdy, but hardly ever deliver any output. The vacuum tube, however, works even under cloudy skies and at lower temperatures.

There are also models that are sturdy (e.g., Buderus). They can even withstand hail. Of course, anything can be damaged... but I have those systems (photovoltaic system, thermal solar) insured anyway...

ares83 schrieb:
One of the providers we still have in our selection just replaced the standard exhaust ventilation system with a mechanical ventilation system this year. Along with a gas condensing boiler. Apparently, that was easier.

Solar energy is great in summer and saves gas. In the end, the solar system costs about as much as the extra gas consumption over 20 years. However, the ventilation system has a real, tangible benefit.

You can always somehow manage to meet KfW 55/70 standard with the technology you want. In the end, it’s just a matter of calculations.

Payday schrieb:
In the end, the solar system costs as much as the additional gas consumption over 20 years

If that were the case, I would be glad.

But it’s not.

Depending on how much you fool yourself, it’s 35-50 years... but that doesn’t really matter. Because by the time it *could* pay off, it will have broken down twice, be fully depreciated... After the first breakdown, I’ll dismantle the nonsense / deactivate it and install 3 photovoltaic cells in its place.

Domestic solar thermal hot water production at these latitudes is complete nonsense and money down the drain. With conventional collectors it’s such a bad idea that you don’t even know where to begin facepalming. For it to work, the sun would have to shine so strongly that you wouldn’t need to take hot baths or showers anymore. In autumn, winter, and spring, it just takes up space on the roof or protects the underlying roof tiles from rain.

That’s why I recommend vacuum tube collectors—if you want or need to do this at all. They at least work when the sky is overcast.

I only have this setup because it was required. It simply doesn’t deliver anything—just costs money and is a nice toy. The cost-saving contribution this system provides is laughably negative, especially considering capital costs. Every wind turbine, every photovoltaic system, is better than this technology, which works great in Italy, Spain, Turkey, the Canary Islands, the Balearics, and the Caribbean. Here, it simply DOES NOT work.

I have also heard of someone who invested over 20,000 euros in such a system for a single-family house with a granny flat, and the technology simply brought him joy.

Maybe it just has to be fun.

PS: For the past three weeks, the unit has delivered practically zero usable energy. Occasionally, it supposedly provided between 1.1 and 3.3 kWh to heat the hot water, naturally charging the bottom of the stratified storage tank. This hardly makes a difference—except that the tank cools down a bit more slowly. Considering losses of around 2.5 to 2.9 kWh per day, it’s almost completely irrelevant.

Such a system works under direct sunlight with no clouds. Here, we might have about 20 days like that per year...

So—the first defect: take it down from the roof along with that junk. There is space for three more photovoltaic panels. That makes more sense, as they can even work during rain… as long as it’s bright enough.

merlin83 schrieb:
Maybe it just has to be fun.

But it’s not — as I said, it doesn’t contribute anything meaningful. Except cost money.

You can build things (including photovoltaic systems) that might cost more than they yield, but at least they yield something.

This ST zero-negative slider thing is slowly driving me crazy in my place here... absolutely terrible stuff.

Half of my utility room is taken up by a hot water storage tank the size of half an indoor swimming pool. It was expensive. Takes up space. High losses due to its size (standby energy). The entire installation. The costs.

Honestly: I had to install it.

But when I see what this device delivers, it’s the biggest bad investment I’ve ever made/had to make.

I also know other homeowners who have this nonsense on their roofs... all just as underwhelmed as I am. Some of them even face directly south, I face east. But don’t think it works significantly better that way...