ᐅ Should the photovoltaic system be taken into account when sizing the heat pump or not?
Created on: 28 Sep 2023 21:34
R
Radfahrer
Hello,
I am considering installing a photovoltaic system.
Currently, my household electricity consumption is about 3800 kWh per year.
Additionally, I have a heat pump with a consumption of around 2900 kWh per year.
Now, I am unsure whether it makes sense to size the photovoltaic system larger to cover the heat pump since heating is mostly needed during the darker months.
In summer, there is probably excess electricity available, which could be used for water heating.
It should also be taken into account that the heat pump usually runs at night in winter and consumes about 3.3 kW.
For water heating only in summer, I would have the option to choose the operating times freely.
However, the air-source pump then requires 5 kW.
Unfortunately, my roof areas are not optimal.
It is a one-story house with a hip roof at 18° (18°) pitch, and the large surface faces almost north.
Three surfaces facing south or west would be sufficient for nearly 10 kWp.
What would you advise me?
I am considering installing a photovoltaic system.
Currently, my household electricity consumption is about 3800 kWh per year.
Additionally, I have a heat pump with a consumption of around 2900 kWh per year.
Now, I am unsure whether it makes sense to size the photovoltaic system larger to cover the heat pump since heating is mostly needed during the darker months.
In summer, there is probably excess electricity available, which could be used for water heating.
It should also be taken into account that the heat pump usually runs at night in winter and consumes about 3.3 kW.
For water heating only in summer, I would have the option to choose the operating times freely.
However, the air-source pump then requires 5 kW.
Unfortunately, my roof areas are not optimal.
It is a one-story house with a hip roof at 18° (18°) pitch, and the large surface faces almost north.
Three surfaces facing south or west would be sufficient for nearly 10 kWp.
What would you advise me?
Photovoltaic system as large as possible. So, even 15 or 18 kWp is fine.
Basically, the system will pay off with the 8 cent feed-in tariff. Also, every green kWh is great!
You can also consider an affordable 5 kWh (17.6 kWh) battery for around 3k. This will significantly increase your self-consumption within 8 or 9 months (200 cycles x 5 kWh = 1000 kWh).
Basically, the system will pay off with the 8 cent feed-in tariff. Also, every green kWh is great!
You can also consider an affordable 5 kWh (17.6 kWh) battery for around 3k. This will significantly increase your self-consumption within 8 or 9 months (200 cycles x 5 kWh = 1000 kWh).
R
Radfahrer29 Sep 2023 18:34First of all, thanks for the responses.
It will probably be similar to building a house.
Equity plus personal contribution plus loan.
I’m not familiar with PVGIS yet.
18° (64°F)
I tried asking for quotes twice.
One didn’t provide a quote at all because I didn’t want a battery.
The second offered a quote with a battery and installation flat rate including scaffolding etc.
Neither the battery nor the scaffolding were wanted.
By now, I’m rather thinking of buying a pallet of photovoltaic modules including mounting brackets through a friend who is an electrical engineer.
The calculation doesn’t add up. 5 kWh storage with 200 cycles (which I doubt) is more like 800 kWh.
Storage losses and usable capacity are often overlooked.
xMisterDx schrieb:
That applies if you have that as disposable money and don’t need to take out a loan.
It will probably be similar to building a house.
Equity plus personal contribution plus loan.
RotorMotor schrieb:
I would recommend entering the data into PVGIS and see which area produces which yield.
If you have difficulties with that, provide more information like orientation and location, then we can help.
But at 10 degrees (50°F), fully utilizing the system often makes sense!
Have you already asked for quotes?
I’m not familiar with PVGIS yet.
18° (64°F)
I tried asking for quotes twice.
One didn’t provide a quote at all because I didn’t want a battery.
The second offered a quote with a battery and installation flat rate including scaffolding etc.
Neither the battery nor the scaffolding were wanted.
By now, I’m rather thinking of buying a pallet of photovoltaic modules including mounting brackets through a friend who is an electrical engineer.
Zubi123 schrieb:
You can also safely get a cheap 5 kWh (kilowatt-hour) storage for 3k. This way you can significantly increase self-consumption again within 8 or 9 months (200 cycles x 5 kWh = 1000 kWh).
The calculation doesn’t add up. 5 kWh storage with 200 cycles (which I doubt) is more like 800 kWh.
Storage losses and usable capacity are often overlooked.
R
Radfahrer29 Sep 2023 18:56The orientation of the house is obviously not optimal.
There is a missing consumption of 478 kWh for the heat pump in January.
R
RotorMotor29 Sep 2023 21:10Radfahrer schrieb:
It’s probably similar to building a house.
Equity plus own labor plus a loan.
By now, I’m leaning towards buying a pallet of photovoltaic modules including mounting brackets through a friend who’s an electrical engineer. If you plan to do the work yourself, I would just order the components cheaply online and then install them.
And if you’re at it, cover the entire roof!
Radfahrer schrieb:
I’m not familiar with Pvgis yet.
18° I meant more the location and orientation of the house, but I think you can see it quite well at the bottom of the image.
South-facing orientations should yield roughly 950 kWh/kWp, and north-facing ones about 750 kWh/kWp.
So it should still be worthwhile for DIY, but not if you buy at high prices.
R
Radfahrer29 Sep 2023 21:57RotorMotor schrieb:
If you plan to do the construction work yourself, I would simply order the components cheaply online and then install them.
And if you’re at it, cover the entire roof! I think so, scaffolding and possibly a forklift could be borrowed from relatives who live less than 100m (330 feet) away.
Angle grinders and drills are available in multiple units.
I’m a bit cautious about ordering online because I don’t know what is cheap junk and what is good quality.
The project will only start in spring; for now, our hopefully pregnant female dog takes priority.
Hello cyclist,
Your post is already a bit old. How did you decide? Is the topic still relevant?
Since February this year, we have had a photovoltaic system on the roof and, of course, obtained several offers. In the end, it always comes down to the price and how much you want to spend. Among other offers, we had one for all four roof surfaces. That was a hefty 48,000€ (about $52,000). That was too expensive for me. For more than two roof surfaces, you also need two inverters, which makes it more costly.
The fact is that a battery storage system increases your energy independence compared to a system without storage. The storage basically serves to cover the household’s energy demand at night. It can also support the heat pump in winter. The heat pump operates with an electric heating element in winter.
Your post is already a bit old. How did you decide? Is the topic still relevant?
Since February this year, we have had a photovoltaic system on the roof and, of course, obtained several offers. In the end, it always comes down to the price and how much you want to spend. Among other offers, we had one for all four roof surfaces. That was a hefty 48,000€ (about $52,000). That was too expensive for me. For more than two roof surfaces, you also need two inverters, which makes it more costly.
The fact is that a battery storage system increases your energy independence compared to a system without storage. The storage basically serves to cover the household’s energy demand at night. It can also support the heat pump in winter. The heat pump operates with an electric heating element in winter.
Similar topics