Consumption study prior to the installation of solar panels

When we start a photovoltaic project in our property, it is essential to carry out a thorough prior consumption study in order to obtain the greatest profitability from our solar panels, as it will directly impact whether the results are optimal and real.

To start this analysis, it is vital to know and understand all the sections that make up our electricity bill, so it is essential to have the receipts for the last 12 months or, failing that, the most recent ones.

Below we indicate the keys to extracting the data correctly and the most important aspects that we must take into account.

Energy consumption of the property

The energy consumed represents a variable term in our electricity bill, so the kWh will increase or decrease in each billing period.

This consumption will allow us to analyze the energy needs of the property, that is, if it requires more electricity at night, in the morning, or if it is regular throughout the day. This will choose the number of solar panels necessary to correctly size your installation and production.

For example, if the property requires more electricity at night than during the day, a lithium battery will have to be incorporated into the installation to store the energy produced by the panels during the day for consumption at night.

Electrical power contracted in the property

The contracted electrical power represents a fixed part that we pay every period in our electricity bill, so it is completely independent of energy consumption

It is expressed in kW and measures the number of electrical appliances that can be used at the same time in the property without causing a power outage or tripping of the leads.

It is a very relevant piece of information when it comes to sizing our solar panels, since it allows us to know the electrical capacity from which we start in order to be able to size the photovoltaic project based on it.

Cost of the property's electricity bill

Finally, we will have to check the price that the consumer pays for the electricity of the property in order to realistically estimate the return on the photovoltaic investment.

It is advisable to first identify if we have a regulated or free contract, as it will allow us to streamline management to a greater extent.

Regulated contract

If the contract is regulated, we will have the PVPC rate, whose price is supervised by the Government every day and every hour based on the existing supply and demand in the wholesale electricity market.

In this case, when carrying out the consumption study it will be necessary to consult the price of electricity today in the BOE, in addition to the average price per kWh paid in recent months. Being such an unstable market, we will obtain a less accurate calculation of the return on investment.

Free contract

If our electricity contract is free, it will be very easy to locate the cost of electricity in the breakdown of the invoices.

In this case we may find ourselves faced with different situations:

– If we have a fixed rate, we will pay a single price for the kWh

– If we have a rate with time discrimination, we can pay two different prices for the kWh (peak and flat) or three (peak, flat and valley)