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Solar Panels = PV Panels ? What are the advantages of using PV panels?

PV panels are the Solar panels. PV panels are very reliable and needs little maintenance. It generates electricity without causing any pollution to the environment, and without the need for any fuel.

Can I connect my PV system to the AC distribution board of the building?

Yes, a PV system with a grid-tie inverter can be connected to the electrical distribution system of the building, provided the system fulfills the technical and safety requirements set by the power company. An application has to be made to the power company concerned for such kind of "grid-connection" arrangement.

Do you know how to measure solar energy performance?

Solar energy potential in a given location is mainly determined by blockage which refers to buildings or objects located directly in the sun's path. Even temporary blockage of sunlight limits the number of hours and days of solar energy in a year.

Solar energy potential is the highest in the summer and on average this figure is relatively steady over the course of a year in Hong Kong.

How to choose PV panels?

Solar Photovoltaic (PV) Comparision: PMG supply PV panels:PV Type: Mono-crystalline (Crystalline), PV Type: Poly-crystalline (Crystalline), PV Type: Amorphous silicon (Thin-film)

PV Type: Mono-crystalline (Crystalline)
Manufacturing method: Made from a single continuous crystal lattice structure
Cell efficiency: 20% - 25%

Equipment Cost: HK$ 24 - 40/ watt
​Advantages:
• Highest efficiency

​Disadvantages:

• Complicated and relatively expensive to manufacture;

• Heavy weight compared to thin-film installation


PV Type: Poly-crystalline (Crystalline)
Manufacturing method: Silicon wafers are produced by casting and saving or by forming thin ribbons directly from the silicon melt
Cell efficiency: 10% - 24%

Equipment cost: HK$ 24- 40/ watt
​Advantages:
• Cheaper than mono-crystalline cells;
• Simpler and less energy intensive to manufacture than mono-crystalline cells;

Disadvantages:

• Less efficient than mono-crystalline cells;

• Heavy weight compared to thin-film installation


PV Type: Amorphous silicon (Thin-film)
​Manufacturing method: Use a homogeneous layer of silicon rather than a crystal structure
​Cell efficiency: 6% - 9%

Equipment cost: HK$ 16 - 24/ watt
​Advantages:
• Cheaper than crystalline cells;
• Can use on curved and flexible surface;
• Light weight

​Disadvantages:

• Less efficient than crystalline technologies

What do you need to consider when installing solar device at home?

You may consider installing solar energy equipment on your roof and/or permanent open areas. For solar photovoltaic (PV) installation, it requires extra space for the inverters and related equipment while minimizing the shaded areas.

For the best results, position your solar energy equipment at an elevated angle of 22.5º facing south.

For further information about technical problems, please visit Technical Guidelines.

What size of a PV system do I need, for supplying standalone loads?

The size of a standalone PV system depends on the loading requirements. Please go through the Solar PV - Application Consideration section of this website to get an idea on how to estimate the size of the PV system required.

How long do PV panels last?

PV panels do not have any moving parts, and normally should last for more than 25 years.

What is Feed-in Tariff (FiT) and RE Certificates?

Under the post-2018 Scheme of Control Agreements (SCAs) with the two power companies, Feed-in Tariff (FiT) and RE Certificates are two important new initiatives to promote the development of distributed RE. FiT will help encourage the private sector to consider investing in RE as the power generated could be sold to the power companies at a rate higher than the normal electricity tariff rate to help recover the costs of investment in the RE systems and generation. At the same time, RE Certificates will be sold by the power companies for units of electricity from RE sources. Through these RE Certificates, the community can show its support for RE. The revenue from the RE Certificates will also help alleviate the overall tariff impact on all consumers brought about by the introduction of the FiT scheme. Apart from the FiT and RE Certificates schemes, the power companies will facilitate grid connection and improve the relevant arrangements.

How long does it take to have the feed-in tariff?

FiT will be offered throughout the project life of the RE systems until end 2033. The electricity generated by the RE systems after 2033 will belong to the RE system owner.

What is Anti-islanding function?

Anti-islanding function

For grid-connected RE power generation systems, anti-islanding function is required to disconnect the RE system in case the part of the grid in the vicinity of the RE system experiences a loss of main power sources.

In the case of a directly grid-connected RE system, the main purpose of anti-islanding function is to prevent the situation where the RE power generation system continues to provide power supply to that part of the grid isolated from the main power sources, thus forming an "island" isolated from the rest of the grid.

In the case of an indirectly grid-connected RE system, the main purpose of anti-islanding function is to prevent the situation where the RE system continues to provide power supply to the loads at the site, when the grid supply to the site is lost. It also prevents back-energization of the grid from the RE power generation system. Furthermore, the anti-islanding function is often required to react quickly to avoid interfering with the auto-switching or auto-reclosing actions on the side of the grid under fault conditions.

Anti-islanding function is usually a built-in function for a grid-tie inverter for PV system.

What is Grid-connected (or grid-tied) PV systems?


Grid-connected (or grid-tied) PV systems in Hong Kong are connected to grid. The AC output of the PV system is connected to the electrical distribution system of a site or a building, and therefore the PV system operates in parallel with the electricity supply from the grid to meet the electricity consumption of the site or building. In this way, storage batteries are not required.