ᐅ Energy Self-Sufficiency – Services Offered

toxicmolotow schrieb:
Who needs more than 1 kWp anyway?

If a system constantly operates at about one-third of its capacity, it covers the entire demand of our base load, and we are not careful at all with standby power, refrigerator, and continuous consumption devices.

Exactly right. That’s how it is for us. I currently have about 260 W base load, with a new refrigerator around 220 W, and with a new freezer added, about 200 W. Beyond that, there’s nothing more to reduce unless you turn off the main circuit breaker.......

Or router, NAS, TV, multiswitch, cable amplifier, thermostats, etc... turn everything off.

toxicmolotow schrieb:
Or router, NAS, TV, multiswitch, cable amplifier, thermostats, etc... turn everything off.

Exactly. When you go through all the points, you realize where at least 50% of the base load comes from... haha. I did all of that because at first I thought: That can't be true. But it is. Small things add up.

At this point, I can really only optimize the fridge/freezer. After that, I've "over-optimized" myself. As of today, there's no more to do... except turning things off. But I still want to live here, not just survive.

Basically, you either go all the way and turn everything off, or you have to accept that 50% of the electricity consumption goes to the baseline load. 250W adds up to 6kWh per day. A small wind turbine that spins slowly but continuously would be ideal for this.

I would recommend consulting a good planner. I have also been researching this topic for some time. I have attended several lectures on wind power, and everything I have learned suggests that it is not worthwhile. The investment in the wind turbine itself is only part of the story. There are several additional components required before the electricity can be fed into the grid, and these are precisely what make small wind turbines uneconomical.

For our build, we will install a large solar thermal system and a 5,000-liter (1,320-gallon) buffer tank. This should cover our needs during the summer. In the colder months, I will heat with firewood (wood is available). This way, I’ll be relatively self-sufficient when it comes to heating.

For electricity consumption, we will install a 10 kWp photovoltaic system on the roof. We are not planning to install an energy storage system at this point, but we will prepare for it. Hopefully, this will make us relatively self-sufficient.

PhiTh schrieb:
We are planning to install a large solar thermal system and a 5,000-liter (1,320-gallon) buffer tank in our build. This should cover the summer months. During the cold months, I will heat with firewood (wood is "available"). This way, I will be relatively self-sufficient when it comes to heating.
For electricity consumption, a 10 kWp photovoltaic system will be installed on the roof. We will not install an electricity storage system at this point but will prepare for it. I hope to become relatively self-sufficient this way.

Very nice contribution from you.

I think self-sufficiency – as of today – never really pays off. It’s a passion of some “enthusiasts” (I’m slowly counting myself among them), not a commercial decision. People who do this cover the costs themselves, which otherwise would be shared by the community.

That’s why I find the wind turbine charming. Costs aside for the moment. It’s about self-sufficiency only; we don’t try to make the numbers look better, we almost don’t calculate them at all (otherwise, I wouldn’t have a photovoltaic system with a battery either).

As we wrote above (f-pNo / me): base load coverage. When I look at the irradiance curves from November onwards, photovoltaics get quite bleak. No matter how large the battery is (aside from the fact that in my micro house with a tiny utility room, I cannot fit a larger battery than the one I have). In a real winter, the large battery will never be fully charged and you have to recharge from the grid (= nonsense).

Just out of curiosity: The 5,000-liter (1,320-gallon) buffer tank is quite a unit… wow… Where are you hiding it? How is it insulated? What are the daily heat losses? (My smaller, 300-liter (79-gallon) high-quality tank in the house needs 2.7 kWh/day just to maintain 50°C (122°F) average, which equals losses.) How large will your solar thermal system be? What type of collectors?

A 10 kWp photovoltaic system without an energy storage system is quite generously sized. You won’t earn much from feed-in tariffs. Are you sure that this size fits your needs? Usually, 5–7 kWp is enough for a single-family house, especially with a south orientation. I almost suspect you want to add a 10 kWh (or larger) battery later, which would make more sense…

Best regards,
Thorsten