ᐅ Is installing solar panels on the roof worthwhile?

We decided against it for two reasons:

a) The payback period is not within 20 years.
b) As Cijay described, the tax-related effort is quite significant. This means you have to file monthly sales tax returns, or at least once a year under the small business exemption. However, in that case, there’s no possibility to claim input VAT back… so effectively, you’re being penalized twice.

Many people I know who installed photovoltaic systems only found out afterward that they also had to submit a tax return. The effort involved for the small amount of savings discouraged me.

In the end, we chose a different approach: we focused on selecting A++ rated appliances, replaced everything with LEDs, avoided leaving lights on unnecessarily, completely switched off devices on standby, unplugged the washer and dryer when not in use, and so on.
And we looked for a cheap energy provider.

The cheapest energy is the energy you don’t use!

raffa schrieb:
Turn off all standby devices completely, unplug the washing machine and dryer after use, etc.

While the previous points are certainly reasonable, I would consider these measures to be excessive. The standby power consumption that is often criticized is actually not financially significant.

We also decided against installing a photovoltaic system. The payback would be just under 20 years since we have a roof area of 16 x 10 meters (52 x 33 feet) facing directly south. However, this assumes no interruptions. Against the potential minimal profit, there are the following disadvantages: roof appearance, maintenance effort, space requirements, heat generation, tax declarations, and possibly increased fire risk.

Knallkörper schrieb:
While the previous points are certainly reasonable, I would consider these measures to be excessive. The often criticized standby power consumption is really not financially significant at all..

I used to think the same until I measured it...

We had standby consumption totaling 35-40 watts with all devices.
Calculate that... 35 x 24 x 365 / 1000 = 306.60 kWh per year standby * $0.25/kWh = $76.65 per year.
With our 8.4 kWp system capacity and our own consumption, we would have saved roughly $350-$400 in electricity costs per year. That means standby power accounts for nearly a quarter of the savings from photovoltaic. For the remaining three-quarters, I compare my own working time spent on the necessary tax return, so that in the end almost no savings remain. Even more so when considering that the photovoltaic system needs to be insured... in the end, you have to be careful not to turn it into a loss.

You can also exaggerate it. A VAT return at this scale isn’t worth more than 5 minutes if you know what you’re doing. Of course, you have to be willing to invest some time in it.
But yes, photovoltaic systems require some ongoing time commitment during operation, whereas solar thermal systems are more of a no-brainer. However, heating system maintenance involves costs (which are not tax-deductible)...

This is more about being forced to do something. And a sales tax return in 5 minutes—please show me how you manage that.

Alex85 schrieb:
There are costs involved in heating system maintenance (which are not tax-deductible...)

Heating system maintenance can indeed be tax-deductible (under certain conditions and not without limits, of course).