For some time now, individuals and professionals have been trying to reduce their energy costs by switching to an electricity provider. This transition offered a temporary reduction in electricity costs. But the energy crisis of recent months has come to show that this is probably the wrong way to deal with the problem.

When PPC (ΔΕΗ) in its low voltage tariffs charged approximately from € 0.10 to € 0.12 per kWh (depending on the tariff), compared to the prices of € 0.085 of some private providers, then the transition to a private provider seemed attractive, as the discount seemed to be 25% or even 30%. Of course, this was half true, as the so-called regulated charges must be added to the cost of electricity, ie the charges related to network usage fees and a series of other types of charges, which are the same for everyone and exceed 0.05 € or even 0.06 €. That is, the charge for a household started from € 0.17 per KWh (with VAT), while for professionals and businesses € 0.18 and € 0.19 (excluding VAT). It is easy to see that the price of € 0.085 per kWh offered by the providers led to a reduction of 16% for households or 23% for a professional, an amount that of course was not at all negligible.

But the energy crisis of recent months has come to reveal the fragile balance on which these benefits acrobatic. On the one hand, the vast majority of consumers had not bothered to read the fine print of the terms of the contracts and on the other hand the companies did not inform their customers about them. Thus the famous “adjustment clause” invaded our daily lives in a dramatic way. What is an “adjustment clause”? The mechanism by which private providers ensure that they will not sell electricity cheaper than they buy it. Specifically, all private providers, but also PPC, stated in the terms of their contracts, that the price they sell electricity will be the one they report to consumers, as long as the price of its wholesale energy remains up to 0, 05 € η kWh. Any increase from there on will be paid by consumers, as an adjustment clause.

It is well known that private providers buy electricity every day from the wholesale market and sell it to consumers. In the last years when the wholesale price of electricity remained below € 0.05 per kWh and so everything worked smoothly. But since the beginning of the year, due to the known increases in the price of gas, the prices of wholesale electricity have risen. The following table shows the average monthly wholesale energy price for 2021: The increases are nightmarish, reaching 40% in December:


Jan-21 € 0.055

Feb-21 € 0.051

Mar-21 € 0.057

Apr-21 € 0.064

May-21 € 0.063

Jun-21 € 0.086

Jul-21 € 0.103

Aug-21 € 0.127

Sep-21 € 0.136

Oct-21 € 0.204

Nov-21 € 0.236

Dec-21 € 0.245

Average Year € 0.119

Obviously, when a private provider bought electricity in December at € 0.245 per kWh, it could not sell it at € 0.085 per kWh. The difference of 0.16 € per kWh is paid by the consumer.

As it is self-evident, no matter what the ads of the recent providers say, in no case can a company buy at € 0.245 per kWh and sell it at € 0.085. It is typical that advertisements are circulating in this period that mention for example, zero clause and a charge of only 0.03 € per kWh. However, they do not tell the consumers that the charge of € 0.03 is above the wholesale price of electricity, ie the charge for December would be 0.245 + 0.03 = 0.275 each € kWh. Other companies offer contracts without a clause for a short period of time (eg 6 months), simply postponing the problem to the future, as they also bind the consumers for the period after the offer, where the adjustment clause will normally apply.

The answer is Net – Metering

So what could be the solution to this heavy bond, especially since prices do not seem to be de-escalating in the near future?

But the obvious: To produce our own energy!

This can be done very easily and without any problems by installing a photovoltaic system under the Net Metering regime. This way you can use the solar energy we enjoy all year round to generate your own electricity and minimize your electricity bill! In other words, you become a self-producer, in the sense that you will produce the electricity that you will consume.

This offsetting between produced and consumed energy (known as Net-Metering) allows the consumer to fully cover his consumption of electricity or part of it, while at the same time he is given the opportunity to use the grid for indirect storage of green energy.

The term “net” derives from the fact that the consumer’s charge / credit refers to the difference between energy consumed and produced in a cycle of counting – pricing of energy consumed. If there is excess energy, it is not lost to the consumer but is credited to accounting for three years at which time the final settlement takes place.

The key points of Net-Metering ine Greece are:

  1. All energy produced by the PV net metering system is used for the user needs.
  2. In case that the solar energy is not enough,
    1. without batteries: the user will also use the gird to extract energy
    1. with batteries: rest of the energy will be drawn from the batteries. When the energy of the batteries is not enough, the rest of the energy will be taken from the public grid.
  3. In case that the energy produced by the PV net-metering system exceeds the used needs,
    1. without batteries: the excess energy is fed to the grid
    1. with batteries: the excess energy will be used to charge the batteries and when they are fully charged, the excess energy would not be lost, but will be fed into the grid
  4. For three years, the energy that you fed into the grid is subtracted from the energy that you got from the grid, so you will be charged only for the net amount of energy that you got from the grid.

In this way we can:

  • You save electricity costs
  • You make yourself more independent from rising electricity prices
  • You can keep track of your electricity consumption, which gives you an overview and helps you save energy and money
  • You can increase the value of your property and protect the environment

In addition to the financial benefits, the installation of a PV system helps to reduce the environmental footprint and is a special tool for promoting your business.

Let’s then look at the financial impact of installing a photovoltaic net metering system on a business, to see clearly the economic benefit that results.

Business: Implementation of a photovoltaic system Net Metering 84 kWp

The effects of installing a photovoltaic self-consumtpion system (Net-Metering) in a Company, with an annual electricity consumption of 121,540 kWh, are examined.

The photovoltaic system will be installed on the industrial roof of the company, which has a slope of 7 degrees and an orientation with a deviation of 9 degrees from south to east. To cover the consumption of 121,540 kWh and taking into account the relevant location, an 84 kWp PV system is required.

A total of 210 PV panels of 400 W each will be placed on the roof and the area they will occupy on the roof is approximately 420 sq.m.

The self-consumption rate is 50%, ie 50% of the production of photovoltaic is led directly to consumption for the needs of the company and 50% is channeled to the electricity grid.

The estimated cost of the photovoltaic net metering system is € 51,000 before VAT, which includes everything (materials, installation, licensing) except the HEDNO connection cost (approximately € 390 + VAT)

Basic Assumptions

  • Annual Consumption: 121,500 kWh
  • PPC Invoice: C22
  • Inflation: 2.00%
  • Photovoltaic Power: 84 kWp
  • Annual drop in PV efficiency: 0.50%
  • Annual Operating Cost: 1.00%


Consumption coverage is as follows:

Net Metring καλυψη κατανάλωσης
Consumption coverage by photovoltaics

The monthly production of the PV system in relation to the monthly consumption is as follows:

Net Metring παραγωγη φωτοβολταϊκο
Monthly production of photovoltaic system and monthly consumption

The economic result from the reduction of the electricity bill, with electricity prices before and after the increases is as follows:

Results50% self-consumption before increases 50% self-consumption with increases
Annual Account without PV21.696 €40.222 €
Annual Account with PV6.573 €6.574 €
1st year benefit from PV15.123 €33.647 €
Benefit for 25 years from PV445.219 €1.001.398 €
economic result from the reduction of the electricity bill due to the photovoltaic net-metering system

The calculation has been made based on the adjustment clause of November 2022 minus the relevant government rebates and consistency rebates. The financial indicators of the investment for the two cases before and after increases have:

Economic IndexBefore increases After increases
Internal Rate of Return (IRR)29.0% 64.8%
Payback period3.5 years 1.5 year
Net Present Value 277,800 €705,600 €
Total 25-year benefit (repaying system and with operating costs) 376,600 €932,800 €
financial indicators of the investment of a photovoltaic net metering system

It is clear that the installation of a self-consumption photovoltaic net-metering system is an extremely profitable investment, even before the current increases. After the increases it has simply become “scandalously” advantageous!

The evolution of the capital level for the 25 years of the investment is as follows:

Net Metring φωτοβολταϊκο στάθμη κεφαλαίου
capital level for the 25 years of the investment

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