Photovoltaic complete system: Which solar system provider is the test winner 2021?

von Sepp Reitberger am 31.10.2021

You want to buy a solar system, but which photovoltaic provider is the best? Efahrer.Com has tested nine -through active providers with six sample cases nine throughout Germany.The differences are huge, the test winner is clear.

For links that are marked with "to the provider" or "to the shop", we may receive.a commission.

Renewable energies start-and you also have to: The Paris climate protection agreement with its strict CO2 emission goals for compliance with 1.5 or at least 2-degree destination requires that the power supply in Germany must make do without coal-fired power plants as quickly as possible.In addition to wind power and planned green energy imports, solar power is one of the pillars of a clean power supply.During the coalition negotiations for the first nationwide traffic light coalition, a possible solar roof obligation was already being discussed that would affect any new building and roof renovation.

It is obvious that this is worth it: the study of an international team of researchers proves that the consistent assembly of all sunlit roofs with photovoltaic modules would be enough to supply the world with electricity.This global approach also applies on a small scale: ordinary single -family houses usually have enough roof surface to cover your own electricity requirements over the year.Very specific: A typical family of four consumes around 3.500 kilowatt hours of electricity a year.In southern Germany, 17.5 square meters of photovoltaics are sufficient to produce this amount of electricity to the south.There is enough space available on single -family houses, but also on semi -detached house halves and on many row houses to install so much power.The additional requirement for an electric car can be harvested analogously on the surface of a normal prefabricated garage via photovoltaics.

With current photovoltaic modules and components (inverter, energy management, etc..))) it is possible to produce electricity for over a term of 25 years at a price of eight to nine cents per kilowatt hour, even if the inverter has to be renewed during the term.The state not only promotes the installation of private photovoltaic systems, it also guarantees a feed-in tariff: electricity that you do not use yourself, you feed on the public power grid and receive a 20-year price of a good seven cent.What sounds like a bad business is very clear when you only use ten percent of the electricity generated - you finally save around 30 cents per kilowatt hour.

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The purchase of a photovoltaic system is unfortunately a bit more complicated than buying a new television: correct planning, correct switching of the individual modules, coordination of the components, all of course to match your own needs, are one thing for professionals.In addition, there is the processing of the funding applications, the registration of the system with the local network operator and finally the regular review and maintenance of the system.

In Germany, hundreds of providers around the end customers compete.Efahrer.Com took a close look.For real comparability, we rate the Internet appearances, the concrete consulting performance, the creation of the offer and the associated service based on six sample cases that cover a wide range of needs: from new construction to younger houses, the expansion of an existing photovoltaicPlant up to real old buildings was there.Our assessment ends with the delivery of the first offer.For all providers, the next step would be an on-site appointment with technicians who specify the offer.These technicians are not employees of the tested providers but local cooperation partners, some of them work together with several of the tested companies, so that no real comparison is possible.At the level of the local craft businesses that take over the actual installation, there is currently the biggest defect: While replenishment of photovoltaic modules works smoothly, it can take several weeks for a on-site date possible.The high capacity utilization of the providers is partly reflected at the very beginning of the advisory process: a consultation did not come about for every test case.In particular, the more complicated cases that mean greater effort for the providers, there were only a few consultations.In this sense, real old buildings, the planned new building and the expansion of an existing system are complicated.

Our comparison gives a good overview of the processes and the quality of the advice and the structure of the offers.

Screenshot zolar.deKlarer Gesamtsieger ist Zolar. Die beste Webseite, der beste Prozess und die gute Beratung bringen den Sieg.

Category 1: Websites

The first contact to the provider is probably in most cases via the company's Internet appearance.In the best case, the website already gives a complete overview of the range of offers, background information on sustainability, the functionality of the system, about technical details, about the various business models (purchase, rent, financing))) and about the legal framework and funding opportunities.The portals should offer an offer calculator that delivers a gross assessment of the costs and income depending on your own consumption and usage profile for different expansion levels of the system.

After all, it is crucial that the website offers the entire range of further contact options and that they can be used without any problems.In this way we rate telephone contact offers the higher the more evening and weekend hours.

None of the offers is perfect.The Zolar portal offers the broadest information spectrum and thus achieves the best evaluation: the website hardly leaves a question unanswered, it is well structured and helps with the start.The offer calculator is only rudimentary for this: it collects initial important information on consumption, equipment and available areas, but for the next step it is already necessary to register with email and real address.The result of the offer calculator is sent by email.

Contact options at Zolar are limited to the days of the week.

Despite these restrictions: With the really complete information offer, Zolar gets the best rating.

Wegatech and Entega are almost equal to second and third place in the website assessment: Wegatech offers a similar profile as Zolar: Very extensive information material is contradictory and an offer calculator that reveals no costs and earnings.Here, too, registration is due before you get this information.

Entega is the counter-design: In the catalog of information that we expect from an online offer, there are no essentials at Entega: for example, information about technical aspects, about the influences of different usage profiles and legal criteria for funding.The focus of Entega is clearly on the offer calculator, which in comparison gives the prospect the best overview of the costs and income of a possible system directly on the website.Entega has the most extensive contact options: The telephone contact reacts Monday to Saturday until 10 p.m. and even on Sunday until 4 p.m..In addition, there is a non -binding contact via chat with an employee.Despite the very different profiles, the interested party applies to the three best rated providers: the prospect receives the information he needs.

2 Bilder Screenshot zolar.deDie beste Website mit dem umfassendsten Informationsangebot hat Zolar zu bieten.

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Category 2: Spectrum of offer

Not every solar provider can meet any customer request.We evaluate the range of offers based on a list of criteria for contract variants (rent/purchase))), technical components such as battery memory or wallbox integration and the possibility to conclude an green electricity contract directly via the provider.

A weak point almost in the complete test field is the topic of heat pump.Heat pumps run with electrical current, they extract the air or the groundwater thermal energy with which they heat up the living room.Modern heat pump heaters produce a heating output of around four kilowatt hours from one kilowatt hour of electricity.The great efficiency and the possibility of operating heat pumps with wind or solar power, for example, make it interesting for the energy transition.There are funding programs for the conversion of real estate stock - and of course the upgrading of a property with photovoltaics is an opportunity to think about a heat pump.

Seven of our nine providers don't see it that way: the heat pump does not matter in its portfolio.Only Entega and Wegatech make suitable offers for the integration of the heating.There are also big differences in the palette of the forms of the contract: DZ-4, Enpal and Entega only offer rental models, which means that the photovoltaic system does not go into possession of the customer for the term of the contract, but the customer paysA monthly fee for electricity use.Only Wegatech and Zolar offer both purchase, financing and rent as a model.

In comparison, Wegatech has the most complete range of offers-only a separate green electricity post is missing for the theoretical maximum number of points.At Zolar, the heat pump integration mentioned is missing in comparison.Together in third place are Entega and Eon, which are restricted in the types of contracts.

2 Bilder Screenshot wegatech.deWegatech bietet bei Vertragsart, einzelnen Komponenten und zusätzlichen Dienstleistungen das breiteste Angebot.

Category 3: Offer process

The complexity of the topic of photovoltaic system is reflected in the processes with which the customer is faced with the various solar providers.For a well-founded and complete advice and subsequent creation of offers, one expert would best have to check all conditions on site: attic and size, possible shading from trees, neighboring buildings or roof structures, built-in materials, roof construction, statics.In addition, there are possibilities in the house: existing electrical installation, empty pipes, the load-bearing capacity of ceilings or walls for heavy electricity storage.The accessibility from the outside finally plays an important role in the effort for the scaffolding building.As the only provider, Sveasolar is trying to actually implement this.For comparability, we also insisted on a telephone consultation at Sveasolar.

All other providers refrain from sending an expert on site in the early advisory phase.And so the companies try to raise as much relevant information as possible in advance.

This includes, for example, uploading images from the roof areas, from the safety box and the electricity meter.In addition, information is queried on the electricity consumption and other criteria.Via the house address and Google Maps or.Google Earth is already possible to estimate which type of photovoltaic installation is possible.

Some providers even try to exclude all eventualities in advance: Wegatech, for example, ask for most individual information about several calls, for example the exact position of satellite dish, exhaust air shafts and fireplace.The Wegatech employees did not want to be satisfied with the first photos of the electrical installation and requested more detailed images.Entega, Enpal and Yello also want to know very well before the first offering of the offer.For example, Enpal wants to see the last electricity bill, Yello even requires a credit check.

With some providers it was also difficult to get a specific appointment at all.DZ-4, ENTEGA and YELLO always owed reactions.In Enpal, additional photos were repeated, the upload of which obviously did not work.There was no further contact in this case - but the emails from the newsletter.A special hurdle at Enpal is that all owners of the property registered in the land register must be present for the consultation.

At Entega and Yello, our testers failed to get a specific consultation and an offer in the given period.Overall, we had the impression that the companies are overwhelmed by the current demand.The positive exceptions were the three best rated providers.

The best picture of the offer process made Zolar: the contact after completing the registration online took a whopping ten minutes in the best case.The appointment for the consultations was easy, the effort for information procurement was within reasonable limits, and the first offer was in the email inbox before the consultation date.

In second place is followed by a still very good rating Clars solar, which questioned a little more information and needed a little longer for the first offer than Zolar.The reliability of the appointment and the feedback were just as convincing.

The impression at Eon was similarly good-but in a test case there were two short-term cancellation of the discussion date (once by the Eon consultant, once by the test customer, who could not notice the new appointment))).The next time we were called, we received the astonishing information that the case was closed.Apart from this outlier, communication with Eon worked reliably and culminated in an offer.

2 Bilder Screenshot zolar.deDer Prozess bis hin zum Angebot läuft bei Zolar wie geschmiert.

Category 4: Consulting interview

The freestyle at our test course is the actual consultation.The conversation should give the prospect the basis for deciding on or against a photovoltaic system and a concrete equipment.This noble claim is not fulfilled by a single provider, rather the consulting appointments are created as sales talks that should convince the customer.This is neither surprising nor reprehensible - but as a customer you should be prepared for advice from a trained seller.

Because the advice depends on the individual employee, we only included providers in the rating where we were able to hold at least three conversations.

Our testers have not been satisfied with the pure sales talk: with targeted inquiries about sustainability and economy, for funding conditions, administrative effort, the specific expiry of the installation and possible disadvantages and reasons that speak against the purchase, they have requested the advice.With expressed uncertainty or doubts, the interlocutors were challenged to prepare good reasons for a degree.

Four weaknesses caught through the bank:

The pure economy was strongly put in the foreground among all providers.Even on request, we rarely received strongly convincing arguments in terms of CO2 savings and climate effects as an answer.Rising electricity prices were guaranteed for economy as guaranteed.

With the exception of Clarsolar, all providers have affected the purchase of a battery store.The simple argument was based on the possible higher self -consumption and on the forecast of rising electricity prices, which at some point led to the electricity from the memory than that from the network.The declarations of intent of politics to slow down the increase in electricity price saves the consultants as well as the fact that the prices for batteries fall strong.In -depth advice must point out that the right time for the purchase of a memory has not yet come.

Very specific requirement profiles were hardly included: A test case with a teacher who is at home in the afternoon, e-car and south-west roof should have clearly led to the house storage.Instead, the car simply appeared in the yield calculations as an additional power consumption, which on the contrary should justify the purchase of a house storage.In this case, we also listed the upcoming exchange of gas heating.This did not influence advice and offer.

The rent rent was offered as risk -free and inexpensive.In fact, financing through the bank is at least equal at the current credit interest level-risk minimization is the only tough argument for rent.Models to buy the system, for example after ten years, are unfavorable for the customer, because after such periods, the risk increases that expensive components will fail with inverters or battery cells.

Despite the similarities, there were clear differences and a clear winner:

The DZ-4 consultants were motivated, listened to almost all questions and were convincing in the conversation.After the conversation was agreed, the respective consultant was easily accessible, the conversations took place in a pleasant atmosphere.Only when it comes to recycling modules and components did the DZ-4 employees have gaps.A very good performance.

We also rate clear solar as very good.All clear solar consultants advised against the purchase of a battery storage and had good arguments for it.Both the questions about sustainability and the financial aspects had larger gaps.

Still very well with a grade of 1.44 Zolar cuts off during advice.The Zolar conversation was very clear a sales talk because it was moving along the previously available offer.However, the offer can be adjusted directly in the conversation at Zolar, for example by varied the size of the house storage, or additional photovoltaic modules are equipped.

2 Bilder Screenshot DZ-4Die Beratungsgespräche von DZ-4 waren umfassend und halfen am besten bei der Entscheidungsfindung.

Overall rating

In the overall ranking there is a clear winner: Zolar wins the comparison with a very good rating.The complete and well-structured information offer on the Zolar website is an excellent start in an almost perfect offer process, which is above all unbeatably fast.But there is also a need for improvement in Zolar: the topic of heat pump heating must be in the advisory repertoire, the consultation should be conducted less as a sales talk.

Second place goes to Eon with the evaluation "good".Opposite Zolar, Eon is particularly noticeable in the availability of information on the website and the offer process.Eon does not work as smoothly as with Zolar.

Third place goes to DZ-4.For the deficit to the two first places, the lack of a purchase option at DZ-4.The offer process is not free of hurdles-not all of our testers came to a consultation or an offer.In the DZ-4 conversation you will be advised for this.One or the other competitor could cut a slice of this.

Solar provider in the test - overall overview

Rang	Anbieter	Wertung	Website (20%)))	Angebots-spektrum (20%)))	Prozess (20%)))	Beratungs-gespräch (40%)))	Link
1.	Zolar	sehr gut (1,3)))	1,0	1,8	1,0	1,4	Zum Anbieter
2.	EON	gut (2,0)))	2,2	2,3	1,8	1,8	Zum Anbieter
3.	DZ-4	gut (2,2)))	1,6	4,6	2,8	1,0	Zum Anbieter
4.	Klarsolar	gut (2,2)))	3,8	3,7	1,5	1,1	Zum Anbieter
5.	Wegatech	gut (2,3)))	1,3	1,0	2,6	3,3	Zum Anbieter
6.	Sveasolar	gut (2,5)))	1,4	4,6	2,2	2,0	Zum Anbieter
7.	Yello Solar	befriedigend (3,1)))	2,6	3,7	4,8	2,1	Zum Anbieter
	Enpal	-	2,7	4,6	3,1	-	Zum Anbieter
	Entega Plus	-	1,3	2,3	-	-	Zum Anbieter

The specials

The specific offers that our testers received for the six cases cannot be systematically compared - the cases and thus the expenses associated with the installation are too different.Overall, we have received too few concrete offers in order to be able to make a fair comparison.

Nevertheless, we analyzed the offers together with an expert: Jochen Kirch from KCE Power Solutions is a dipom engineer and publicly appointed and sworn expert for the Fachdann photovoltaic.In this role, he is regularly consulted as an appraiser for legal disputes about photovoltaic installations, for example in the case of installation errors or if the provider's earnings forecast is optimistic.Jochen Kirch is also an electromobility planner and supports companies in the integration of charging options into their electrical infrastructure.

The analyzed offer from DZ-4 was created for a fairly new house with a large south roof.Overall, the offer looks plausible and well -founded.Unfortunately, there is no precise derivation for the earnings calculation included: it is not clear whether possible shading has been included correctly.The information is included in the offer.

DZ-4 includes the possibility of buying the system after ten years.Around 50 percent of the new price is scheduled for this.Such a residual value is certainly justified for the photovoltaic modules, but not for memory and inverter.With these expensive components, one should assume that they have to be replaced within 15 years.After ten years, more than half of the expected lifespan has passed.

The distributed rental offer is not complete in terms of contractual details (who is a business partner, what happens at the end of the rental, if the system is not bought, what early exit options are there, what happens if a roof renovation is necessary during the termbecomes?))).This information will of course be in the contract, but would also have to be listed in detail on the offer.

Enpal only offers the rent and is more detailed with the rental conditions on offer.Overall, the offer looks plausible and correct-with one exception: The cost of maintenance, maintenance and insurance are included for comparison for comparison..The rental model contains all of these costs, the comparison costs that are too high make the rent appear more attractive than it is.

Eon provides a detailed earnings calculation with.As with DZ-4, it is not clear how exactly the data basis of the calculation is because a derivation is missing.It is not clear whether possible shading is included.

Eon makes a clear mistake in the earnings calculation: Eon does not start with maintenance costs when calculating the duration of the amortization.It will be approx..It takes two years longer than stated before the system has paid off via the electricity saving.A rarely contained, but important point, Eon has carefully careful: the creation of a precise documentation of the system.In the case of possible repair work by third parties, this is essential, the company that installs the system is therefore obliged to document.Nevertheless, she sometimes fails.

The offer of Clarsolar is well structured and quite complete, but also clear solar calculates numbers that are not plausible-in the case of fashion grade (i.e. the performance loss per year))), the offer is too pessimistic.The underlying 0.5 percent per year conflict with the practical experience with current photovoltaics.Realistic are 0.2 to 0.3 percent.Clear solar is too optimistic about the maintenance costs: 1930 euros will not be enough to pay the maintenance for 20 years.In the case of cost accounting, Clarsolar sets up60 percent self -consumption in the rated offer.For this test case, we have distributed electricity consumption throughout the day (home office))), but without battery storage it is unrealistic to achieve this high value.

In his offer, Sveasolar explicitly lists the analysis of roof geometry and shading.The basis is a measurement by laser on site.However, there was no on-site appointment with the owners, because we also insisted on telephone advice and preparation for the offer at Sveasolar.Presumably these are standard formulations that should have been removed in our offer.

Nevertheless, the income calculation of Sveasolar has a plausible effect, the offer is fine overall.

Wegatech is transparent when calculating the yield: The basis here is the calculation solution of PV*SOL, in which a precise solar yield atlas is stored for Germany, and which is calculated very precisely with a roof orientation and tendency.

This is exactly how the electricity income calculation is: In terms of economic calculation, Wegatech has set a price increase of three percent per year.In view of the plans of the traffic light coalition to limit the electricity price, the profit that is too much too highly scheduled is likely.

The documentation in the offer is also listed at Wegatech.

Zolar's offer is dynamically stored on the provider website, the customer has the option of selecting different powerful modules or components, and configuring the memory size-or omitting the memory.

Zolar's rated offer refers to a house with three roof areas that are combined (east and west side of the house, also the flat roof of the ready-made garage))).For the optimal use of all areas, Zolar has provided an expensive inverter from Solaredge, which can operate each module with optimal performance.

Zolar calculates a separate consumption share of 40 percent without memory-regardless of whether a wall box for the electric car is added that is not.In the analyzed case it was stated that the electric car is in the garage and connected in the afternoon-this would have to be much higher that would have to be self-consumption.

Unfortunately, we did not receive a specific offer from Yello and Entega during the test period.

Two things that are legally relevant can be noted for all offers: the procurement of information about static requirements and the specific roof substructure is the responsibility of the client.The customer must take care of this information.Of course, the installer is also obliged to inquire and include this information.

Jochen Kirch has a drastic example of what can happen if this information is not incorporated correctly: a solar system on a roof with a saving insulation, in which the thickness of this insulation was too low.As a result, the screws to assemble the module brackets did not reach the load-bearing wooden beams, but simply ended in the insulation.After a few storms, the photovoltaic modules were loose.

A second, essential point concerns the damage to roof tiles during assembly.Only Eon, Klarensolar and Wegatech have listed this topic at all-but as a client, you should have clarified in any case before the conclusion, who has to procure replacement roof pans in the event of damage, and up to which number of damaged pans can be loaded at costs.

Screenshot zolar.deDas Angebot von Zolar ist dynamisch - der Kunde kann es selbst anpassen.

The most important questions and terms for the photovoltaic test

So hatEfahrer.com tested the photovoltaic providers

With six sample cases behind which five real houses and a planned house building are stuck, we have started the process for a solar system offer via the providers' websites.The cases covered the entire range from the real old building with questionable statics, to middle-aged houses to the fast new building, in which a small photovoltaic system is already installed.Some of the roofs have a clear southern orientation, partly combinations of east and west roofs as well as a ready-made garage roof are available.

The evaluation of the providers runs along the way to create a first offer.

The first point in the evaluation is the provider's website, the website assessment flows into the overall ranking with 20 percent.For the websites, we check on the basis of over 50 individual criteria, how extensive the provider's information offering is how extensive the contact options are and whether the website already gives a first option to calculate the possible system size and earnings.

The second evaluation point is the range of offers, which also flows into the overall ranking at 20 percent.In addition to the possible types of contracts (rent, purchase, financing))), this deals with the technical components that the provider can integrate into a possible system (z.B.House memory, wall box, heat pump connection))) and additional services such as an adapted green electricity contract.

The evaluation of the overall process also goes into the overall ranking with 20 percent.Here we assess the accessibility, reaction speeds, the type of information recording and provision by the provider (such as instructions for uploading photos of house, roof areas, installation, etc..))).

The freestyle is the consultation, which finally has to make the basis for the purchase decision.The conversation goes into the overall ranking with 40 percent.In over 20 criteria, we evaluate the Enlightenment on sustainability, financial aspects, legal framework, for service, for the specific expiry of the installation etc..

In all sub-areas we create a relative assessment in percent, the best provider sets the 100 percent mark.We implement the percentage values in school grades (100 to 90 percent: very good, 90 to 75 percent: good, in 15 steps the evaluation goes up to "insufficient")))).The overall ranking is calculated via the specified weighting from the individual schoolnotes.

Does a house memory make sense?

The motivations for the installation of a photovoltaic system differ very much-the motivation depends on the sensible equipment, and complete advice should be extensively discussed with this point.A house memory made of battery modules and a corresponding energy management system is actually never economically sensible.A short overlapping bill: The house memory offered are in the area of approx..700 euros per kilowatt hour capacity. Die meisten Anbieter gewähren eine Garantiedauer von zehn Jahren, bei der aktuellen Lithium-Eisenphosphat-Technik sehen die technischen Daten meist 250 volle Ladezyklen pro Jahr vor (das heißt: ein vier kWh großer Speicher setzt im Jahr 250 x 4 kWh elektrischer Arbeit um, bei sinnvoller Dimensionierung ist dieser Wert auch erreichbar))), über zehn Jahre ergeben sich also 2.500 full cycles for the memory.A kilowatt hour of battery storage facilities deliver 2 in the ten years.500 kilowatt hours of electricity.Save the current then costs 28 cents per kWh over the ten years - almost as much as a kWh of electricity costs today.Sure: a lithium iron phosphate battery will probably last longer than ten years, basically the technology is up to 10.000 cycles suitable.As a user, you will not be allowed to hope for the 40 years of service..An investment that has only re -recorded its costs after 20 to 25 years is not economical - especially since it can be expected in such a long time frame that the first components (Z.B. Wechselrichter))) ausfallen und teuer ersetzt werden müssen.

Most providers in the test nevertheless present an earnings calculation in which a memory is worthwhile: they simply assume that they are increasing increasing electricity prices - sometimes two percent increase per year, some five percent.Even at a two percent annual increase, the current electricity price from 30 cents per kilowatt hour would increase to almost 45 cents in twenty years.A five percent increase per year was led to a price of 48 cents per kWh in ten years, in 20 years there would be almost 80 cents.

Even with such pessimistic assumptions for electricity price development.System integrators or car manufacturers in China LFP battery cells can already be bought for less than 100 euros per kilowatt hour today.Even if such prices cannot be compared to end customer prices in Germany, this shows that there is a lot of air down.Further developments and the strong expansion of global manufacturing capacities will probably continue to press the battery prices further.For example, it would be economically sensible to wait until batteries are available for 250 euros per kilowatt hour.With the invoice above, there would be a surcharge of ten cents per kWh for stored electricity.Then the memory is expected to be worthwhile.

So a house memory is not yet suitable for saving money.Nevertheless, many homeowners choose the battery because they achieve a certain independence: independence from the electricity supplier, for example, i.e. self -sufficiency in the event of power outages.

According to the interference statistics of the Forum Netztechnik/network operation of the VDE, the German electricity customer had to live on average with 10.2 minutes of power failure in 2020.Despite all the calls and catastrophe scenarios due to the phase -out of the nuclear phase -out and the high ride of volatile renewable energy sources, the power supply in Germany is more reliable than ever before.If you are concerned with bridging these statistical ten minutes, you have to make sure when purchasing the house storage.Standard inverter, which produces the DC a Cabbago 230 VOLT AC.Only explicitly emergency powerable systems are not dependent on this external reference and can be operated completely self -sufficient.

Anyone who is seriously planning to use the memory for the emergency power must also avoid optimizing the self-use of the PV current: If you consistently use the electricity from the battery during the eveningMore is available.A real emergency power bridging is a very expensive pleasure.As a customer, you should know very well that you need and want to pay for it.

Another restriction can limit the benefits of a house storage: Not every energy management system can combine the power from the storage and photovoltaics can combine it as desired.Standard systems can often only make the electricity from photovoltaics available on the socket or the electricity from the battery-not both at the same time.If you then want to load an electric car, for example, while photovoltaics only supply a kilowatts of power, then such systems can only load the car with electricity from the battery or from the power grid.The photovoltaic then remains unused.

With the offer of a power storage alone, not all conceivable use scenarios are covered.If you want to implement a certain application, make sure that the corresponding functions in the offer are explicitly listed.

Does it make sense to combine e-car and photovoltaics?

Electric cars with average driving requirement (in Germany: approx..13.000 km pro Jahr))) verbrauchen pro Jahr 2.500 to 3.000 kWh of electricity, over 80 percent of the needs can be covered by normal users on their own charging connection.In principle, the purchase of an electric car is therefore the perfect time to think about a photovoltaic system.However, if you are traveling by car every day, for example to work, and therefore only load at home from evening to the morning, you don't have much potential to use your own PV current at first glance.

It is worth taking a closer look at the needs scenario here: is the car more in the morning or in the evening at home?Can photovoltaics make a contribution in the corresponding hours?Depending on the dimensioning of the system and the weekly mileage, the weekend can be sufficient to recharge the car again.An optimally planned facility with ten kilowatts of peak power can be almost 3 on weekends alone.Generate 000 kilowatt hours of electricity.If the battery in the car is large enough to hold out for a working week, then you can actually generate a large part of the car requirements.One of our test cases represents an even cheaper scenario: Modules with 4.4 kW peak performance can be placed on the west southwest side of the roof, the owner is a teacher and therefore mostly at home in the afternoon.A large part of the electricity generated can therefore be loaded directly into the car.

Our test shows that the providers do not approach the task with the offered differentiation: electric cars are generally simply included in the calculation with their electricity consumption.Occasionally it is possible to indicate the expected loading times for the car.Following the logic of most offers, an electric car infected in the evening would be loaded from the house memory until it is full.On the other hand, it would make sense to use a control, which primarily loads with electricity excess from photovoltaics, with that more loading time is available at the weekend and ensures that a specified minimum battery level in the morning is achieved.To a certain extent, the more complex energy management systems can provide these functions.However, the possibilities are limited: Type 2 wall boxes for your own garage have no interface for the transmission of the charging status from the car-a control that is based on the charging status is therefore not, which means that the optimal loading behavior of manual interventionsrequirement.

BYDHausspeicher kosten rund700 euros per kilowatt hour capacity und sind noch nicht wirtschaftlich. Die Preise fallen aber schnell.

What does peak performance mean?

The real yield of a photovoltaic system in kilowatt hours depends on countless conditions: for example, the sun and ray duration, the stem angle and the temperature.In order to be able to compare the photovoltaic modules of different manufacturers, the electrical performance is measured under defined laboratory conditions.The peak performance of a complete system is obtained by multiplying the performance of a module with the number of modules. Wenn die Module verschiedene Ausrichtungen aufweisen (zum Beispiel Ost- und West-Dach))), dann kann der angegebene Peak-Leistungswert in der Praxis gar nicht erreicht werden.

In Germany, the peak performance of times 1.Attack 000 hours.This means that a system with6.4 kWp approx..6.400 kilowatt hours of electricity delivers.Browned photovoltaic modules with an area of almost two square meters deliver up to 0.4 kilowatts of peak performance.

What is the feed -in tariff?

You can feed electricity from your photovoltaic system, which you do not consume yourself.The electricity meter does not simply run backwards, but the powered electricity is specially recorded and remunerated.Private systems up to a maximum output of ten kWP, which are registered in November 2021, receive 7.04 cents per kilowatt hour over a period of twenty years. Nach dem Ablauf der 20 Jahre kann der Eigentümer seinen Strom entweder auf dem freien Strommarkt anbieten (organisiert über darauf spezialisierte Agenturen))) – oder versuchen, mit einem Hausspeicher oder zusätzlichen Verbrauchern gezielt den erzeugten Strom zu verwerten.

What is the 70 percent rule?

This rule states that operators of a photovoltaic system with defined remuneration may only feed up to 70 percent of the peak performance of the system.The background to this regulation is the fact that the yield from optimally south-facing photovoltaic installations has a pronounced climax at lunchtime.Due to the 70 percent rule, the maximum of daily electricity production is extended-the electricity yield is better planned and usable for the network operators.At the same time, the 70 percent rule is a motivation to design the system right from the start in such a way that it can deliver electricity over the longest possible period of time-for example by setting up the east and west of a roof.The entire electricity generated can then be fed up correctly.

What is an energy management system?

Distribution of the electrical energy between the mains connection, photovoltaics, house memory and domestic consumers is not a trivial task - if only because photovoltaics and battery stores work with DC, while the network and consumer require alternating current.The energy management system controls the optimal flow of energy and, for example, can ensure that surplus current beyond the 70 percent rule is specifically loaded into the house memory or into an electric car.

Does shading of the modules make problems?

Shadows on the photovoltaic modules affect electricity generation.Depending on the design and switching of the modules, a fireplace or satellite antenna can fail a whole series of modules because the modules are usually switched into series.A shady module then acts as a resistance.Modern modules have bridging diodes that are not designed for permanent loads.When planning a photovoltaic system, every possible shadow throw must be included.During the decades of runtime, growing trees or even new buildings in the neighborhood can become a problem.For systems with several areas and possible shading through different objects, it makes sense to use an inverter that can address and use all modules in parallel.The efficiency of such inverters is somewhat lower than with standard inverters, which is more than the optimal use of the modules than.