at icon
phone icon
+48 791 050 578
European Union Content
FAQ - frequently asked questions
Here are some of the most frequently asked questions with answers.
How do I order Greto products?

Simply contact the company's sales department and ask for a full quotation for a specific product. You can also contact us by email or by filling in the contact form. You can find all contact details here. Some products can also be ordered online by registering in the Greto Customer Panel and selecting a specific device.

I have sent an enquiry. How long will it take to receive a reply?

We try to reply to all messages as quickly as possible, but no longer than within 24 hours.

Is it possible to purchase only 1 or a few panels?

The minimum order for photovoltaic modules is 1 full pallet.

How many modules are on one pallet?

Jest to zależne od konkretnego modelu modułów. Standardowo jest to 31 lub 36 sztuk.

What is the delivery time of the order?

The lead time can depend on several factors, and the operations department determines it precisely depending on specific conditions. However, there are general elements that affect lead times. 

Elements that directly affect the lead time include:

Form of payment: Delivery time may depend on the time when the payment for the order is credited. Please check GRETO's terms and conditions of sale, where specific payment terms should be specified.

Delivery Location: delivery time may depend on the delivery location provided by the customer. Geographical distances and transportation conditions may affect the delivery time.

Delivery time: Delivery time may also depend on circumstances such as holidays or day of the week. Depending on where the goods are taken from and the destinations, logistics can be adjusted to account for these issues.

Equipment availability: If the customer has the right equipment for unloading, this can reduce lead times, especially for large or unusual deliveries.

Standard delivery from specific locations is as follows:

Orders from Greto warehouses: Once the money has been credited to the account, the products are dispatched on the second working day. Within Poland, delivery is approximately 2-3 working days. For other European countries it is individual depending on the location.

Container orders of modules from Rotterdam: From the booking of the payment, we collect the container from Rotterdam within 2-5 working days. Delivery to the customer within Europe, is another 2 working days.

Customised products (modules):  At Greto, we also offer customer-specific deliveries. Any module produced by our suppliers (JA Solar, AE Solar, HD Hyundai, Trina Solar, Canadian Solar) can be ordered in container quantities after payment of a 10% production deposit. Waiting time is approximately 3 months.

Is it possible to collect the products in person?

This may be done on the working day following the day on which Greto has credited the sales price together with other charges payable by the Customer in connection with the Order. Personal collection of the Equipment is possible during working hours of the warehouse (no later than 1 hour before its closing date) under the conditions described in the preceding sentence and after an additional avocation of the person collecting the Equipment made by e-mail to the relevant employee of GRETO and containing the number of the Order, the name of the person collecting the Equipment and the registration number of the car.

Is it possible to reduce delivery costs?

Yes, it is possible to reduce shipping costs, but this is highly individual, depending on many factors. The key is to understand that shipping costs can be reduced depending on various scenarios.

First of all, a customer increasing the number of devices ordered can potentially reduce shipping costs. This means that more products can be transported at once, which can translate into savings in logistics costs.

By and large, it can be said that in most cases, as the number of units of goods ordered increases, transportation costs tend to decrease. In the case of PV, having a forklift at the site of unloading (for orders of more than 4 pallets) can be an additional factor in reducing shipping costs, although this is not always necessary.

Ultimately, the final assessment of the possibility of reducing transportation costs should be carefully reviewed with the transportation company, taking into account all the details of the order, delivery distance and other logistical factors.

What courier / shipping company are orders delivered by?

We carry out courier shipments through companies such as RABEN, DSV and DHL. When it comes to dedicated transportation, we select an experienced carrier for the destination.

What if the shipment arrives damaged or incomplete?

Appropriate photo documentation will be required and visible damage/defects will be noted on the CMR document or waybill.

We enclose a ready-made damage report template with each parcel or pallet. We recommend filling in the data directly on this document (available in two language versions; Polish and English).

If it is a courier consignment and there is a possibility - you can refuse to accept the delivery due to damage in transit.

What payment methods are available?

The method of payment carried out in Greto Polska are bank transfers. You can pay in EUR, PLN, USD

Will the VAT invoice for the order be included in the shipment?

Invoices are sent electronically to the email address

Where can I find the warranty card for a particular product?

All documents such as datasheet, warranty and instructions are available on our website or can be sent to your email address after contacting the sales team.

Could I get technical assistance, such as selection of panels, inverter, optimizers?

If you have any doubts about the selection of the device for your requirements, our sales representatives with a technical specialist will help you choose the optimal solution.

How does the possible complaint of the goods proceed?

Within 3 days from the date of delivery of the Equipment other than photovoltaic modules to the Customer, the Customer shall be entitled to withdraw from the Sales Contract for the said Equipment in part or in whole and to return them. They must be returned to Greto in undamaged, original packaging and without signs of use. 

The aforementioned term of withdrawal and return of the Equipment is observed if, before its expiry, the Equipment is delivered to Greto's address: Greto Polska Sp. z o.o., 5/20 Kielecka Street, 81-303 Gdynia. The Customer will attach a statement/return protocol to the parcel, which will contain: the Customer's data, date of purchase, data (including the type and number) of the returned Equipment and data for the transfer of the returned amount.

All claims under the guarantee shall be submitted to the manufacturer of the Equipment through Greto in accordance with the terms and conditions specified in the guarantee document.

Need more information? We encourage you to check the terms and conditions of sale

Is it possible to purchase the installation with installation?

Greto as a distributor does not provide installation services. If you are looking for a trusted installer in your area we can recommend companies that work with us

What type of wallbox charger should I order for my client?

W celu doboru ładowarki, należy w pierwszej kolejności sprawdzić zastosowany rodzaj wtyczki. W większości europejskich i amerykańskich samochodów stosowana jest obecnie wtyczka typu 2. Następnie należy sprawdzić dostępną sieć elektryczną pod kątem dostępnej mocy i rodzaju sieci elektrycznej (jednofazowa lub trójfazowa).

How to choose the power of a heat pump?

To properly select a heat pump, you need to calculate the energy requirements of the building. With new buildings we have such information in the construction project. For buildings in operation in which we will be doing a heating modernization, it is best to use the audit service, which will show us exactly what heat pump power will be optimal for the building. This will allow us to optimize operating costs and the investment itself. The power of a heat pump consists of many factors, such as the surface of the house, the thickness and type of insulation, the operating temperature of the heating system.

How to choose energy storage?

Electricity storage should be selected in terms of connectivity, planned energy consumption, the purposes of its use and financial possibilities.

Does energy storage guarantee energy independence from a public energy supplier?

Tak, instalacja fotowoltaiczna hybrydowa może zapewnić zasilanie elektryczne wielu urządzeń w domu również w przypadku zaniku prądu w sieci energetycznej dostawcy.

What is the life span of a heat pump?

It is expected that a properly installed and operated heat pump should last about 20 years.

Will the heat pump heat even at low temperatures?

Yes, the heat pumps in the GRETO range work down to -25*C!

What is half-cut technology?

Half-cut technology is a technology for making the photovoltaic cells that make up a module. The goal is to cut the cell in half in order to reduce the current flowing through the cells, as well as to work better during shading.

What is busbar?

Busbars are vertical connectors that link photovoltaic cells in a module

What is the difference between monocrystalline and polycrystalline modules?

Polycrystalline modules are made of silicon blocks, while monocrystalline modules are made of single silicon. Monocrystalline modules have higher efficiency, especially during periods of low sunlight.

What is the difference between an inverter and a microinverter?

The micro inverter is located near the PV module and supports 1 to 8 PV modules simultaneously. On the other hand, a classic inverter supports chains of modules (usually 18 modules in a chain) and quantities that allow from 0.8 kW to as much as 330 kW of power.

What is a hybrid inverter?

The hybrid inverter, in addition to converting energy from photovoltaic modules, also allows charging and discharging of electrical energy storage