Dear forum members,
I am new here and, to be honest, I haven’t read all the previous posts yet, so a similar topic might already be discussed.
We are a family with three small children and are fortunate to be allowed to build in our hometown near Regensburg. In 2011, we built a small 145 sqm (1,560 sq ft) Tuscan-style house, but unfortunately, it no longer meets our needs, so we are planning to build again. Our current home is heated with a groundwater heat pump including cooling (which we rarely use). Overall, we are satisfied with the heating results, although on cold winter days, I miss the comfortable “warm feet feeling” that I have experienced with friends who have pellet or gas heating. What bothers me more is that our hot water takes quite a while to heat up and only reaches a temperature where I can still comfortably keep my hand under it.
We are considering a pellet heating system, but to be honest, we haven’t really researched heating systems at all yet—and a lot has probably changed in the last eight years. Our architect has proposed a compact heat pump with a central ventilation system and hot water storage, as this would likely be cheaper than a pellet system with central ventilation. However, for the heat pump, we definitely do not want an outdoor unit. An indoor installation might be possible, but we have concerns about the noise.
Is a central ventilation system really necessary or required? Currently, we have a decentralized ventilation system, which works well overall, but I am quite bothered by the plastic covers inside, which have yellowed over time.
What are your experiences? Ventilation—yes or no?
Heating—pellet, compact unit, or something else?
Thank you very much!
Best regards, Stefanie
I am new here and, to be honest, I haven’t read all the previous posts yet, so a similar topic might already be discussed.
We are a family with three small children and are fortunate to be allowed to build in our hometown near Regensburg. In 2011, we built a small 145 sqm (1,560 sq ft) Tuscan-style house, but unfortunately, it no longer meets our needs, so we are planning to build again. Our current home is heated with a groundwater heat pump including cooling (which we rarely use). Overall, we are satisfied with the heating results, although on cold winter days, I miss the comfortable “warm feet feeling” that I have experienced with friends who have pellet or gas heating. What bothers me more is that our hot water takes quite a while to heat up and only reaches a temperature where I can still comfortably keep my hand under it.
We are considering a pellet heating system, but to be honest, we haven’t really researched heating systems at all yet—and a lot has probably changed in the last eight years. Our architect has proposed a compact heat pump with a central ventilation system and hot water storage, as this would likely be cheaper than a pellet system with central ventilation. However, for the heat pump, we definitely do not want an outdoor unit. An indoor installation might be possible, but we have concerns about the noise.
Is a central ventilation system really necessary or required? Currently, we have a decentralized ventilation system, which works well overall, but I am quite bothered by the plastic covers inside, which have yellowed over time.
What are your experiences? Ventilation—yes or no?
Heating—pellet, compact unit, or something else?
Thank you very much!
Best regards, Stefanie
Lumpi_LE schrieb:
Seriously, @Bookstar, where do you get so much nonsense from?
The gas price increase from 50 to 200 is a bit exaggerated, but other than that, I can only agree with the rest. You see, I ask myself the same about your posts. My arguments are based on facts, but photovoltaic enthusiasts tend to ignore those.
Fact 1: Return and risk:
“The DAX return triangle demonstrates that over an investment horizon of 20 to 30 years, the annual return in the past ranged between six and nine percent. Short- and medium-term price fluctuations in stocks are compensated over these periods.”
Apparently, the current political developments have also passed you by, but go ahead and keep dreaming of your great returns that do not exist.
With a laughable feed-in tariff of 12 cents, you won’t even achieve a positive return unless you factor in self-consumption. And if electricity prices drop significantly, your calculations will be wrong. Nobody guarantees otherwise.
Thanks to a heat pump tariff, I pay significantly less for electricity than usual—and without installing such a device on my roof with all its disadvantages.
guckuck2 schrieb:
The profitability of a photovoltaic system is completely independent of the electricity price development. I have already told hampshire that. Let’s quickly go back to energy consumption. If I feed in 2500 kWh at 10.5 cents (With current commissioning, the fastest can have it installed on the roof in 3-4 months, so we should be there) instead of using it myself, I pay, let’s say, 25 cents per kWh for that electricity. Then I would rather consume this power myself. So I can increase my return by using the energy, and the higher the electricity price rises, the higher the return becomes. Or where is the flaw in my reasoning?
B
boxandroof29 Jun 2019 10:08That is absolutely correct. Higher energy consumption increases the already high return.
However, you cannot consume everything yourself, and photovoltaic systems are profitable even without energy consumption, but only under unusual circumstances when relying solely on consumption. Increasing the share of energy consumed via storage is certainly appealing, but is still considered very uneconomical.
It is obviously illogical that surplus energy production in summer can be sold at the same prices as the much smaller amounts in winter, and the same applies when purchasing energy. But that’s how it is, and this is exactly why photovoltaic systems are profitable through subsidies.
However, you cannot consume everything yourself, and photovoltaic systems are profitable even without energy consumption, but only under unusual circumstances when relying solely on consumption. Increasing the share of energy consumed via storage is certainly appealing, but is still considered very uneconomical.
It is obviously illogical that surplus energy production in summer can be sold at the same prices as the much smaller amounts in winter, and the same applies when purchasing energy. But that’s how it is, and this is exactly why photovoltaic systems are profitable through subsidies.
hampshire schrieb:
For example, covering the house’s base load, lighting, computers, starting cleaning machines early in the morning when the rooftop solar power isn’t sufficient yet...But I wouldn’t buy expensive photovoltaic for that; I’d rather pay for regular electricity.H
hampshire29 Jun 2019 10:28It’s actually quite simple.
Reasons to install a photovoltaic system are varied:
Economic benefits include:
When weighing concerns or deciding between different systems, considerations include:
Almost exclusively, economic aspects are discussed here, which is too narrow a view. I would not install standard photovoltaic modules on the roof that look unattractive, always involve two trades on the roof, generate unhealthy high voltages, pose a fire risk to the building, and reduce the home’s value upon resale – who wants to buy in 15 years a house disfigured by old, obsolete, and ugly photovoltaic panels?
We invest in the appearance of our homes, consider colors, shapes, and materials, and then slap ugly boards on the roof – just because we cannot get out of the ingrained “penny-wise, pound-foolish” payback mindset. Build homes that you like and that enable healthy, comfortable living. With or without photovoltaic systems.
From 2022 onwards, nobody talks about whether to install photovoltaic systems, but rather which photovoltaic system will go on the house. That is when the low-energy building regulations take effect.
- The feed-in tariff decreases month by month. The registration date is what matters. The 12 cents are long gone. For registration in July 2019, it was still 10.64 cents for a system under 10 kWp.
- Energy prices in Germany continue to rise. Relevant information can be found, among others, from the BMWi. With a heat pump tariff, current rates are around 20–25 cents, while a standard tariff averages about 29 cents.
- A kilowatt-hour that is self-produced and self-consumed is more profitable than one that is self-produced and fed into the grid.
- According to simple logic, self-consumption is more advantageous than feeding electricity into the grid – and this is also the political intention.
- Photovoltaic power output depends on solar irradiation (Reliable conservative irradiation data is provided by PVGIS, an EU service).
- Household electricity consumption is not linear, neither throughout the year, nor within a day or an hour.
- Batteries as energy storage systems are used to optimize self-consumption by compensating for missing photovoltaic output in the short term and overnight, eliminating the need to draw power from the grid.
- Photovoltaic energy is ecologically beneficial if the components are environmentally produced – ROHS-certified components contain neither lead nor cadmium and are recyclable. (Not all photovoltaic modules meet these criteria.)
- Standard photovoltaic modules were never designed specifically for roof installation. They are connected in series and generate very high voltages, which brings challenges such as fire safety, electromagnetic exposure, structural considerations, and the involvement of two trades during all work and repairs on the roof...
Reasons to install a photovoltaic system are varied:
- Attitude toward environmental issues
- Desire for greater independence and autonomy from price developments
- Economic benefits
- Meaningful integration into a home energy concept
- …
Economic benefits include:
- Feed-in tariff / payment for surplus electricity
- Reduction of grid electricity consumption
- Preservation or increase of property value (questionable with standard modules)
- …
When weighing concerns or deciding between different systems, considerations include:
- Health (electromagnetic exposure)
- Recyclability
- Service life
- Payback period
- Change in property value
- Effort in case of repairs
- Aesthetics of the building
- Knowledge of self-consumption behavior (not just annual consumption…)
Almost exclusively, economic aspects are discussed here, which is too narrow a view. I would not install standard photovoltaic modules on the roof that look unattractive, always involve two trades on the roof, generate unhealthy high voltages, pose a fire risk to the building, and reduce the home’s value upon resale – who wants to buy in 15 years a house disfigured by old, obsolete, and ugly photovoltaic panels?
We invest in the appearance of our homes, consider colors, shapes, and materials, and then slap ugly boards on the roof – just because we cannot get out of the ingrained “penny-wise, pound-foolish” payback mindset. Build homes that you like and that enable healthy, comfortable living. With or without photovoltaic systems.
From 2022 onwards, nobody talks about whether to install photovoltaic systems, but rather which photovoltaic system will go on the house. That is when the low-energy building regulations take effect.
Bookstar schrieb:
You won’t get a positive return with a ridiculous feed-in tariff of 12 cents alone; self-consumption must be included. That’s not correct. Even assuming the inverter needs to be replaced after 10 years, we would still be in a positive range relying only on feed-in. And thanks to the pitched roof, our two-roof system with 6.3 kWp is actually designed more for energy consumption.
Similar topics