ᐅ Operating a heat pump independently with a photovoltaic system.
Created on: 18 Dec 2015 19:51
I
Inotsara
Is there a photovoltaic expert here? Preferably an engineer specializing in this field? I am an electrician myself but have not yet had any practical experience with photovoltaic systems. So far, I only know about them theoretically and am very enthusiastic. I want to dive deeper into this topic and prepare myself for practical work. Recently, I have been looking into inverters and especially battery storage. The more I read, the bigger the gap I feel needs to be filled.
Currently, I am working on a project involving my parents' air-to-water heat pump. It’s a newly built house with two living units. The combined electricity consumption of both units is about 2200 kWh. Additionally, the pump consumes approximately 6600 kWh per year. Naively, I assumed my parents could invest around 25,000€ in a 9 kWp photovoltaic system and achieve a self-sufficient setup with very low electricity costs (about 30€ per month instead of 180€).
But that’s not the case. Firstly, a single-phase storage system is not an option because, due to the technology and grid regulations, the pump relies on the other two phases and will ALWAYS draw power from the grid. Even with a three-phase battery storage system, this problem would only be theoretically circumvented but not completely solved. Especially in winter, the pump runs at 80%-100% capacity while a photovoltaic system generates only about 30%-35% of its output in winter. In summer, the situation is almost exactly the opposite. This means we would underproduce in winter and overproduce in summer. On top of that, a three-phase battery system costs twice as much, and the number of manufacturers offering this option is very limited.
So, my question to the real experts: Should I just discard the idea of making the heat pump fully independent, or have I missed something?
I have gained a lot of knowledge in recent days through phone conversations with an engineer who is also a salesperson. However, I feel a bit uncomfortable bothering him further. He has already explained a lot to me. Also, information in written form is always better because you can look things up repeatedly and add to your knowledge. Therefore, it would be great if we could share our knowledge here together =)
Currently, I am working on a project involving my parents' air-to-water heat pump. It’s a newly built house with two living units. The combined electricity consumption of both units is about 2200 kWh. Additionally, the pump consumes approximately 6600 kWh per year. Naively, I assumed my parents could invest around 25,000€ in a 9 kWp photovoltaic system and achieve a self-sufficient setup with very low electricity costs (about 30€ per month instead of 180€).
But that’s not the case. Firstly, a single-phase storage system is not an option because, due to the technology and grid regulations, the pump relies on the other two phases and will ALWAYS draw power from the grid. Even with a three-phase battery storage system, this problem would only be theoretically circumvented but not completely solved. Especially in winter, the pump runs at 80%-100% capacity while a photovoltaic system generates only about 30%-35% of its output in winter. In summer, the situation is almost exactly the opposite. This means we would underproduce in winter and overproduce in summer. On top of that, a three-phase battery system costs twice as much, and the number of manufacturers offering this option is very limited.
So, my question to the real experts: Should I just discard the idea of making the heat pump fully independent, or have I missed something?
I have gained a lot of knowledge in recent days through phone conversations with an engineer who is also a salesperson. However, I feel a bit uncomfortable bothering him further. He has already explained a lot to me. Also, information in written form is always better because you can look things up repeatedly and add to your knowledge. Therefore, it would be great if we could share our knowledge here together =)
oleda222 schrieb:
Links are not allowed here anyway... Then you will have to take my word for it. My photovoltaic system will cost approximately 15,000€ (rounded), with a repayment subsidy of 5,000€ (approximately). Over 20 years, without the photovoltaic system, I would pay around 18,000€ in electricity costs assuming a constant electricity price of 0.27€ per kilowatt-hour. However, that is quite unrealistic. I expect the price to rise to about 0.40€ per kilowatt-hour in 20 years, which would further increase electricity costs.
Tesla Powerwall 6.3 kWh + BenQ 21 x 280 W = 5.88 kWp
ONeill schrieb:
Caution: unconfirmed hearsay – don’t current batteries have a half-life of 8–12 years?
5,000 to 10,000 charge cycles. So it depends on your usage patterns. Some manufacturers also offer extended warranties. After 10 years, battery storage systems will probably cost only half as much and perform twice as well, making it financially worthwhile then as well. The higher your current electricity costs, the more it makes sense to install a system. But there are certainly experts who might disagree. For me, it’s enough that I’m convinced.
Sascha aus H schrieb:
Would you like to explain what exactly is included in the interior finishing? Finishing up to drywall installation and screed. Everything beyond that is the homeowner’s responsibility. This includes tasks like filling and sanding, installing flooring, tiling the bathroom, and so on.
toxicmolotow schrieb:
And what does this system cost monthly? How about taxes?
In the end, it’s not cheaper, but also not more expensive. Without storage, it’s basically just moving money from one pocket to another... And after 10 to 14 years, we can say it’s "worth it."Why monthly? Do you mean the installment for the loan taken out for it?Similar topics