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I very much want one of these in Finland, but our provider KSOY said no no no. Posing the question, is there a valid technical reason or is it just institution

I very much want one of these in Finland, but our provider KSOY said no no no. Posing the question, is there a valid technical reason or is it just institutional conservatism and inertia ?

Lichtso 2y ago
Operating electrical power grids requires a very careful balance between production and consumption. Long term trends are regulated on the consumption side through pricing, short term jitter is regulated on the production side through switching power plants on and off. Traditionally, a power grid only had medium and large power plants, and they are not only connected to the power grid but also a control network. Adding many small power generators poses a problem in how you communicate and coordinate with them. "Connecting Solar to the Grid is Harder Than You Think" https://www.youtube.com/watch?v=7G4ipM2qjfw https://www.youtube.com/watch?v=7G4ipM2qjfw
- Gasp0de 2y ago
  Although 800w per household shouldn't make a difference for the grid.
  - bluGill 2y ago
    800w for your house won't make a difference. Multiply by millions of households and that is real power that will make a difference.
    - tweepy 2y ago
      You could think the other way around: what prevent every citizen from a region to switch ON or OFF a 7kW load at the same time (such as an EV)
    - Gasp0de 2y ago
      800w is the maximum being produced, and not all of it will be fed into the grid. And it is unlikely that millions of households have all installed powerplants which are all oriented in the same direction and not shaded.
      - bluGill 2y ago
        Germany is 84 million people. If 1% have solar and they currently average to 400 watts (half capacity from their 800 watts because of positional and shading issues) that is 33 Gigawatts. That much power if not managed will cause problems for any grid.
        Gasp0de 2y ago
        No, if 1% of them produce 400w that is actually only 320 Megawatts.
rjsw 2y ago
I got the feeling that people were just not telling their electricity provider that they were doing this.
Trellmor 2y ago
These things just plug into a power outlet. Requirement for Austria is a Smart Powermeter, because the old, analog ones would run in reverse if the solar panels produced more then you are currently using. They may not exceed 800W and are required to turn off if no power grid is detected, e.g. during a power outage. Apart from that, just institutional conservatism and inertia as far as I know.
Ekaros 2y ago
Because they are potentially deadly in certain failure states. Normally system you expect system to be dead when main switch is turned off. But in this case something might be feeding in power. Same goes for over current protection. You really do not want power when you expect there to be none. Even if you should always check.
- floitsch 2y ago
  Balcony solar requires the 50Hz of the energy grid. If you turn off the main power they will stop feeding into the system.
  - tengbretson 2y ago
    So if enough of your neighbors have these panels then the grid never gets turned off.
    - WJW 2y ago
      Technically probably yes, provided you had millions of neighbors, the sun never sets and all big users like kettles and heat pumps kindly switch off as well. If either of those conditions stops being true, then either the frequency or the voltage will drop too much and the panels turn themselves off. In practice these balcony panels are not sufficient in the slightest to power a house, let alone an entire apartment building, and they will turn off almost instantly.
- Limeray 2y ago
  [dead]
- the-unknown-dev 2y ago
  This is not really an issue. The inverters used in these cases rely on an existing power supply for synchronization with the electrical grid. If there is no power on the socket, the inverter has no means to generate a sine wave on its own and does not provide power on its cable. This is true (as far as I know) for ALL inverters, apart from "off grid" solutions, so workers can turn off power on a street level. If that wasn't the case, there would be no way for technical staff to make sure that lines going to multiple homes (with solar) are powered off.
InDubioProRubio 2y ago
Have your cake and eat it ? https://solarbringer.de/solar-inselanlage-mit-netzunterstuetzung/ https://solarbringer.de/solar-inselanlage-mit-netzunterstuet...
- ccozan 2y ago
  Yes, this is exactly my configuration! 3.5kw panels, 9kwh battery. Saves at least 1/2 of the daily power usage.
thefz 2y ago
In any given moment the power grid must be 1:1 for production and consumption, and lots of smaller renewables pose a problem for big operators because they need to forecast and balance.

I very much want one of these in Finland, but our provider KSOY said no no no. Posing the question, is there a valid technical reason or is it just institutional conservatism and inertia ?

Lichtso 2y ago

Operating electrical power grids requires a very careful balance between production and consumption. Long term trends are regulated on the consumption side through pricing, short term jitter is regulated on the production side through switching power plants on and off. Traditionally, a power grid only had medium and large power plants, and they are not only connected to the power grid but also a control network. Adding many small power generators poses a problem in how you communicate and coordinate with them. "Connecting Solar to the Grid is Harder Than You Think" https://www.youtube.com/watch?v=7G4ipM2qjfw https://www.youtube.com/watch?v=7G4ipM2qjfw

Gasp0de 2y ago
Although 800w per household shouldn't make a difference for the grid.
- bluGill 2y ago
  800w for your house won't make a difference. Multiply by millions of households and that is real power that will make a difference.
  - tweepy 2y ago
    You could think the other way around: what prevent every citizen from a region to switch ON or OFF a 7kW load at the same time (such as an EV)
  - Gasp0de 2y ago
    800w is the maximum being produced, and not all of it will be fed into the grid. And it is unlikely that millions of households have all installed powerplants which are all oriented in the same direction and not shaded.
    - bluGill 2y ago
      Germany is 84 million people. If 1% have solar and they currently average to 400 watts (half capacity from their 800 watts because of positional and shading issues) that is 33 Gigawatts. That much power if not managed will cause problems for any grid.
      - Gasp0de 2y ago
        No, if 1% of them produce 400w that is actually only 320 Megawatts.

rjsw 2y ago

I got the feeling that people were just not telling their electricity provider that they were doing this.

Trellmor 2y ago

These things just plug into a power outlet. Requirement for Austria is a Smart Powermeter, because the old, analog ones would run in reverse if the solar panels produced more then you are currently using. They may not exceed 800W and are required to turn off if no power grid is detected, e.g. during a power outage. Apart from that, just institutional conservatism and inertia as far as I know.

Ekaros 2y ago

Because they are potentially deadly in certain failure states. Normally system you expect system to be dead when main switch is turned off. But in this case something might be feeding in power. Same goes for over current protection. You really do not want power when you expect there to be none. Even if you should always check.

floitsch 2y ago
Balcony solar requires the 50Hz of the energy grid. If you turn off the main power they will stop feeding into the system.
- tengbretson 2y ago
  So if enough of your neighbors have these panels then the grid never gets turned off.
  - WJW 2y ago
    Technically probably yes, provided you had millions of neighbors, the sun never sets and all big users like kettles and heat pumps kindly switch off as well. If either of those conditions stops being true, then either the frequency or the voltage will drop too much and the panels turn themselves off. In practice these balcony panels are not sufficient in the slightest to power a house, let alone an entire apartment building, and they will turn off almost instantly.
Limeray 2y ago
[dead]
the-unknown-dev 2y ago
This is not really an issue. The inverters used in these cases rely on an existing power supply for synchronization with the electrical grid. If there is no power on the socket, the inverter has no means to generate a sine wave on its own and does not provide power on its cable. This is true (as far as I know) for ALL inverters, apart from "off grid" solutions, so workers can turn off power on a street level. If that wasn't the case, there would be no way for technical staff to make sure that lines going to multiple homes (with solar) are powered off.

InDubioProRubio 2y ago

Have your cake and eat it ? https://solarbringer.de/solar-inselanlage-mit-netzunterstuetzung/ https://solarbringer.de/solar-inselanlage-mit-netzunterstuet...

ccozan 2y ago
Yes, this is exactly my configuration! 3.5kw panels, 9kwh battery. Saves at least 1/2 of the daily power usage.

thefz 2y ago

In any given moment the power grid must be 1:1 for production and consumption, and lots of smaller renewables pose a problem for big operators because they need to forecast and balance.