How it works:
According to the Net-Billing method, the producer-consumer uses the production of electricity from the PV system solely for Net-Billing and therefore he will be compensated for the surplus electricity is returned into the grid. Any energy produced that is not used for self-consumption but is returned to the grid will be counted by a meter which will be installed by EAC or any other supplier. This surplus will credit to the producer on a variable tariff knownas the avoidance cost. The PV power of each system must range from 10 kW to 10000 kW per applicant and per unit.
What should be taken into account during the design of the PV system?
In order to select the proper size of the PV system that will be installed the annual consumption of the load profile of each premise, as well as the expected produced energy of the PV system, which will be calculated using simulation programs for that specific area, must be taken into account. It is very important to calculate correctly the size of the PV system, so that adjusted to the real electrical needs of each premise. Therefore a precise design and accurate evaluation of the PV power of the system is required to find the optimal solution for the customer's consumption profile, in order to avoid unnecessary expenses. This will affect the usable energy that can be consumed by the producer-consumer from the PV system. Petrolina Solar Ltd, with its lengthy experience in both the study and installation of PV systems, provides its customers with a free in-depth study in terms of their needs and their consumption profile providing all the information they need to know before installing a PV system.
In addition to the above, our Company connects a data logger if it's needed into the existing electrical installation for a certain period of time, which records data per minute. This detailed data helps us to create an accurate and reliable study and choose the appropriate size for the PV system. Some of the collected data is the total power consumed by the premise, the power per phase, the total energy consumption.
Where can such a system be installed and how much surface area does it need?
A PV system for the production of electricity for Net-Billing can be installed on flat or inclined roofs of existing legitimate-constructed premises or within the plot in which the consumer’s premises are located and/or adjacent plots. Attention must be placed on the choice of the installation area of the PV modules to avoid any shading, especially during the hours of 9 a.m. - 3 p.m.
For the installation of 1 kW PV system on inclined roof, with PV modules size 1.69 m x 1.00 m, a net surface area of about 5 m2 is required. Thus a 20 kW power system, for example, requires a 100 m2 surface.
For the installation of 1 kW PV system on a flat roof, with PV modules size 1.69 m x 1.00 m, a net surface area of about 10 m2 is required. Thus a 20 kW power system, for example, requires a 200 m2 surface.
Who can apply for Net-Billing PV system?
Any individual or legal person whose premises have a commercial or industrial tariff has the right to apply for a Net-Billing PV system. This includes commercial and industrial units, public buildings, army bases, schools, agricultural and livestock units, and fishing enterprises with the purpose of producing electricity for their own use. Also, a Net-Billing PV system can be installed in any premises of an individual physical person (residences).
What is the cost of the PV system and what are the annual savings?
The cost of the PV system in this category cannot be predicted in advance, since it should be preceded a precise study and design in terms of the energy needs of each individual case. Our Company visits each facility to record the data and measurements needed to prepare an offer and to complete the design and detailed study of the PV system at no financial cost to the consumer-producer.
EAC requires the installation of a data logging and recording device for both the production and consumption separately. The cost of buying and installing these meters is fully paid by the consumer-producer.
In order to estimate the annual savings a detailed study based on the customer's consumption profile is completed to calculate the amount of produced energy and the time of consumption. Each case is treated individually and tailored to the needs of the consumer.
The techno-economic study that we prepare, considers the operational expenses of the PV system such as existing network charges, as determined by CERA, the insurance and the maintenance costs of the PV system.
What is the process for licensing/approval and for the operation of the PV system?
We undertake the whole procedure for licensing/approval for the PV system. We will only require some documents from the applicant as the title deed of the plot or the building, a building permit, a plot layout plan, etc. The first step is to submit an application to CERA to obtain an exemption from a construction license. If the power of the PV system is greater than 20 kW a building permit for the PV system must first be obtained. For a PV system with a power greater than 150 kW the following documements are required: 1) Planning Permit and 2) Environmental Study.
Once CERA has issued the exemption from a construction license, an application is submitted to EAC to issue the terms for the connection. Once the customer has signed the terms, installation with our Company is scheduled.
Upon completion of the installation, the last step is to arrange the inspection of the PV system by EAC. With the success of the inspection and the issuance of the certificate of suitability by EAC, we submit an application to CERA for the exemption from operation licence. Once this license is obtained and the contract with EAC is signed we are ready to start the operation of the PV system.
Example of a PV system of 500 kWp – Net-Billing-factory
Example of a 500 kWp PV system that operates according to the Net-Billing plan. This particular PV system has a Fronius smart meter. The continuous black line shows the production of the PV system on a specific day. Red is the energy consumption that was not covered by the PV system but supplied by the grid. Grey colour shows the consumption covered by the PV system.
For this specific day:
99% self-consumption from the PV system
56% coverage of total consumption
For the same example, green colours show the energy produced by the PV system which was not consumed by the factory and fed into the grid. As in the above graph, in grey, we can see the consumption covered by energy generated from the PV system. The continuous black line shows the total energy consumption by the factory on that day.
Example of a PV system of 15 kWp – self consumption-offices
Example of a 15 kWp PV system that operates according to the self consumption plan. This particular PV system has a Solaredge smart meter. Green is the production of the PV system on a specific day. Red is the energy that was not covered by the PV system but supplied by the grid. Light blue shows the consumption covered by the PV system.
For this specific day:
95% self-consumption from the PV system
53% coverage of total consumption