Introduction to Photovoltaics (New Construction)

It makes sense, if you want to generate a large part of your own consumption yourself, to use only the combination of photovoltaics and the associated storage system. However, the problem is that both together are too expensive – in other words, you end up paying more per generated and stored kWh than if you were to get it from the grid.

Whether it is economically worthwhile over the lifespan (storage systems and photovoltaic systems do break down eventually) depends on what electricity price you speculate on in the future. The general opinion here is that it is not economically worthwhile today and that prices would have to "explode" for it to make sense.

One kWh of self-generated electricity, stored in a power storage system and then drawn from it, costs at least 40 cents. More likely more. Photovoltaics alone are quite profitable. Self-consumption is more worthwhile than feeding in, therefore it basically makes sense to store. But not with the available technologies today.

I am currently also considering switching from a gas condensing boiler and solar to a gas condensing boiler and photovoltaics with the option of retrofitting a storage system later (possibly in 10 years). I think that still "pays off" more than solar... at least I intuitively see the ROI here as more favorable.

On the other hand, I seriously wonder how one can consume 3,500 kWh with a family of three (in an apartment?).

With a gas condensing boiler combined with photovoltaics, the question is how you implement the requirements of the Energy Saving Ordinance regarding a renewable share for heat generation. To bring photovoltaics into play, for example, buffer storage tanks with heating rods are needed. In principle, for direct heating "immersion heater" is too wasteful for photovoltaic electricity in my opinion, solar thermal is more efficient in this regard. Controlled residential ventilation with heat recovery can provide the renewable share. Photovoltaics with heat pump seems to be a nice combination.

On the other hand, I seriously wonder how you consume 3,500 kWh with a family of three (in an apartment)?

Quite simple: older freezer, regular cooking and baking, an aquarium or terrarium, a child who often forgets to turn off the lights, various standby devices (TV, receiver, PlayStation, ...), use of a dryer... And suddenly you're quickly at 3900 kWh. So it's no big deal.

On the other hand, I seriously wonder how you can consume 3,500 KWh with a family of three (in an apartment?)?

Oh wonder :) Some manage 7500 as two..ok now as three we consumed 8500 last year.