Good morning,
Yesterday, we received a quote for a photovoltaic system. Our construction of the single-family house will start in October 2023 and is expected to be ready for occupancy in September 2024.
We have an annual electricity consumption of about 3000 kWh for our household, plus an unknown amount for the air-to-water heat pump (Weishaupt Biblock).
Our roof is oriented exactly south with a 25° pitch (gable roof). According to the calculation in the quote, the entire south roof is fully covered with modules (20 units), and the north roof is also equipped with 5 modules.
Attached you will find the details of the quote. The price is €20,900 net with battery storage and €15,900 net without storage.
What do you think of the offer? From what I understand in the discussions here on the forum, it is advisable to skip the battery storage. That would bring the cost to just under €16,000, which is a bit over €1,600 per kWp. That seems relatively expensive, doesn’t it?
Thank you very much in advance for your help.
Best regards,
Elias
Yesterday, we received a quote for a photovoltaic system. Our construction of the single-family house will start in October 2023 and is expected to be ready for occupancy in September 2024.
We have an annual electricity consumption of about 3000 kWh for our household, plus an unknown amount for the air-to-water heat pump (Weishaupt Biblock).
Our roof is oriented exactly south with a 25° pitch (gable roof). According to the calculation in the quote, the entire south roof is fully covered with modules (20 units), and the north roof is also equipped with 5 modules.
Attached you will find the details of the quote. The price is €20,900 net with battery storage and €15,900 net without storage.
What do you think of the offer? From what I understand in the discussions here on the forum, it is advisable to skip the battery storage. That would bring the cost to just under €16,000, which is a bit over €1,600 per kWp. That seems relatively expensive, doesn’t it?
Thank you very much in advance for your help.
Best regards,
Elias
E
Elias_dee27 Jul 2022 09:41Thank you both for the input. It's true, taxes on feed-in are missing. The consumption might indeed be optimistically calculated, BUT the electricity price at €0.35 (35 cents) is also optimistic... I hardly believe that electricity will still cost €0.35 (35 cents) in 10 years.
It's always somewhat of a bet on the future. Of course, the calculation with a south-facing system only makes the model more profitable, but I’ve also often read here in the forum that you should fully equip the north side, especially if you have an air-to-water heat pump.
By the way, PVGIS shows me around 11,000 kWh for 10 kWp south-facing and about 7,400 kWh for 10 kWp north-facing...
It's always somewhat of a bet on the future. Of course, the calculation with a south-facing system only makes the model more profitable, but I’ve also often read here in the forum that you should fully equip the north side, especially if you have an air-to-water heat pump.
By the way, PVGIS shows me around 11,000 kWh for 10 kWp south-facing and about 7,400 kWh for 10 kWp north-facing...
R
RotorMotor27 Jul 2022 09:59Elias_dee schrieb:
Electricity price at €0.35 is also... I hardly believe it will still be €0.35 in 10 years. Well, unfortunately no one can say for sure.
Looking at the electricity prices in neighboring countries, I wouldn’t be so sure that prices in Germany will rise significantly.
But who knows. ;-)
Elias_dee schrieb:
It’s always somewhat of a bet on the future. Obviously, the calculation only makes the south-facing model more profitable, but I have often read here in the forum that you should fully cover the north side as well, especially if you have an air-to-water heat pump. You can fully cover the north side if you have a flat roof.
So up to about 20 degrees. And the recommendation comes from a time when 1 kWp cost €1,000.
Elias_dee schrieb:
By the way, PVGIS gives me about 11,000 kWh for 10 kWp south-facing and around 7,400 kWh for 10 kWp north-facing... Ah, that means you must be located quite far south.
But with over 30% less yield, and current prices increased by around 50% (plus the extra effort for mounting), the economic viability is questionable...
And the equipment would also be better placed on a neighbor’s south-facing roof. ;-)
E
Elias_dee27 Jul 2022 10:03RotorMotor schrieb:
Well, unfortunately no one can say for sure.
Looking at electricity prices in neighboring countries, I wouldn’t be so certain that prices in Germany will increase significantly.
But who knows. ;-)
For a flat roof, you can do full installation facing north.
So up to about 20 degrees. This recommendation comes from a time when 1 kWp cost 1000€ (about $1100).
Ah, then you must be coming from much further south.
But with over 30% less yield, combined with currently about 50% higher prices (plus the effort for mounting systems), economic viability is hard to achieve...
And the materials would be better used on a south-facing roof of your neighbors. ;-)I understand your points. So you wouldn’t install anything facing north at that price? Previously, there was always the argument about bypassing the 70% cap, which has now been removed as of 01/01/2023...
Another option could be to keep the south-facing system at 10 kWp and install only 3-5 kWp on the north side, all running through a single inverter instead of the two currently included in the offer?
R
RotorMotor27 Jul 2022 10:12Elias_dee schrieb:
I understand your points. So, you wouldn’t install anything on the north side at that price? Previously, there was always the argument about bypassing the 70% shading limit, which no longer applies as of 01/01/2023... Exactly, that doesn’t make sense anymore.
Elias_dee schrieb:
Would another option be to keep 10 kWp on the south side and only do 3–5 kWp on the north side, all running through a single inverter instead of two, as currently proposed? No, that won’t work either, because the string voltage wouldn’t be correct.
My opinion is to just install on the south side, and if prices and the market calm down, you can still add the north side later.
Since it’s basically two separate systems with two inverters anyway, it doesn’t make sense to do it now at these inflated prices.
Do you have a garage, carport, or patio roof you could install panels on?
KingJulien27 Jul 2022 10:17Why choose a north-facing elevation? Isn’t flatter better?
Or is the 21 degrees the optimum angle suggested by PVGIS?
A north orientation then significantly increases self-sufficiency for about half the year.
You really have to calculate that precisely. Best to consult the experts.
Or maybe "our guy" can chime in, @Deliverer 😉
Or is the 21 degrees the optimum angle suggested by PVGIS?
A north orientation then significantly increases self-sufficiency for about half the year.
You really have to calculate that precisely. Best to consult the experts.
Or maybe "our guy" can chime in, @Deliverer 😉
R
RotorMotor27 Jul 2022 10:32KingJulien schrieb:
Why actually tilt north? Isn’t flatter better there? We’re talking about north orientation. Adjusting the tilt from 25° to 20° (degrees) is an option you can consider.
Whether it makes sense, I’m not so sure. But I’m certain there will be shading issues.
Has the solar installer simulated that?
Because although PVGIS shows higher yields, in reality they usually turn out significantly lower.
KingJulien schrieb:
Tilting north also significantly increases self-consumption for half the year.
You really need to calculate that precisely. Best done by the professionals.
Or maybe “ours” can share their input, @Deliverer 😉 Whether that increase is significant is debatable. ;-)
Especially in winter, the low sun angle means the north-facing panels won’t receive much sunlight.
Similar topics