Grid Bill Savings Simulation

The simulations offered on PVGIS.COM are designed to meet the varied requirements of professionals as well as individuals in the solar-energy sector. This service is supported by a consortium of European solar experts and engineers, ensuring truly independent and neutral expertise. Here are the main stakeholders and objectives covered by the simulations.

The PDF example below is in English. Your own report will be automatically generated in the language you selected in your account settings.

Save on Grid Bills Simulation

Download the PDF sample

Solar radiation and photovoltaic production will vary if there are local hills or mountains that block sunlight at certain times of the day. PVGIS can calculate their effect using ground elevation data with a resolution of 3 arc-seconds (about 90 meters). This calculation does not consider shadows from very nearby objects like houses or trees

PVGIS 5.3 provides a default value of 14% for the total losses in the solar electricity generation system.

PVGIS24 Simulator proposes a loss value for the first year of operation. This loss will evolve year by year. This first-year loss value allows for a more detailed technical and financial analysis, year by year. Thus, over a 20-year operational period, the total production loss is close to 13% to 14%.

The result of the photovoltaic energy calculation: is the average monthly energy production and the average annual production of the photovoltaic installation with the chosen properties. The inter-annual variability is the standard deviation of the annual values calculated over the period covered by the selected solar radiation database.

Monthly solar irradiation Is determined for each hour of the day for a selected month, with the average being calculated over all days of that month during the multi-year period for which PVGIS has data. In addition to calculating the average solar radiation, the daily application of radiation also computes the daily variation of clear-sky radiation.

The hours of monthly photovoltaic energy production represent the total time over a month that a solar installation produces of electricity, influenced by sunlight, system efficiency and operating conditions. It is a key indicator for evaluating performance and energy self-sufficiency.

This analysis uses a method designed to evaluate energy consumption and its cost over a defined period, segmenting the data into monthly and daily averages.

Basic data: The total annual energy consumption (kWh) is distributed by month to examine the variability of demand; the associated cost is determined based on a unit purchase rate.
Temporal breakdown: Monthly and daily averages provide a detailed understanding of consumption fluctuations throughout the year; an average percentage reflects each month's relative contribution to the annual total.
Purpose: This method helps identify periods of high or low consumption and plan strategies for energy optimization or cost management. Provide a clear and actionable overview of energy consumption to improve the sizing of solar installations or storage systems while keeping energy costs under control.

This analysis is based on a theoretical approach aimed at estimating the financial savings associated with solar energy self-consumption, relying on annual consumption and photovoltaic production data.

Energy consumption breakdown: The total consumption is segmented by time periods (weekdays, weekends, daytime, evening, nighttime) to assess the specific energy needs for each time slot. This approach helps identify daytime consumption, which reflects the potential for self-consumption.

Estimation of self-consumption potential: The solar production estimated by PVGIS is compared with daytime consumption. The coverage percentage indicates the portion of daytime consumption that can be directly supplied by solar energy.

Calculation of financial savings: Self-consumed kWh are valued based on the energy purchase tariff to calculate annual savings.

This analysis provides a quantitative basis for evaluating the financial benefits of self-consumption and optimizing the size of solar installations. This method also helps identify key periods to maximize the use of the energy produced.

Solar Production

Indicates how much your system can produce and how this production changes over time. This helps estimate your savings and any potential income.

Consumption

Shows your level of electricity usage. By comparing it with solar production, you can visualize your self-consumption capacity and your dependence on the grid.

Grid Tariffs

Help you understand the benefit of consuming your own electricity rather than buying it, and the long-term impact of price increases.

System Cost

Presents the actual price of the installation after subsidies and helps you assess the required investment.

Financing

Explains the available payment options and how to plan your budget.

→ Long-term savings

Shows the total savings generated by the solar system over several years.

→ Self-consumption rate

Indicates the share of solar energy directly used by the household.

→ IRR (Internal Rate of Return)

Measures the overall financial performance of the investment.

→ ROI (Return on Investment)

Indicates how long it takes for the initial investment to be offset.

A histogram comparing solar production and energy consumption offers several advantages for analysis and decision-making, especially in the context of energy optimization

To maximize profits: Cash financing is ideal but requires mobilizing funds immediately.

To preserve capital: A loan offers a good solution, with moderate financial costs, with or without an initial contribution.

To facilitate financing: Leasing is a quick and balanced option; however, despite a slightly lower IRR, high interest reduces the profit.

→ Electricity Bill (Grid Bill)

This section shows how your electricity bill evolves over the years based on:

your consumption,
the price of electricity,
and yearly grid price increases.

It helps visualize the gradual increase in energy costs without solar.

→ Loss of Purchasing Power (Depreciation)

This table shows how inflation reduces your purchasing power over time. It illustrates that the same amount of money is worth less each year.

→ Why Solar Matters

By combining both tables, the key takeaway becomes clear:

grid electricity prices increase,
your purchasing power decreases,

→ producing your own energy becomes a form of financial protection.

→ Annual Solar Production

Shows how production changes slightly from one year to the next. This is the basis for all financial calculations.

→ Self-Consumption

Indicates the share of energy you use directly at home. This self-consumed energy saves you the grid electricity price.

→ Annual Economic Balance

The “balance” column shows whether the system generates a net gain or a net cost each year, taking into account:

self-consumption,
savings achieved,
and expenses.

→ Cumulative Gain Over Time

Illustrated by the columns on the right, this tracking shows from which year the system becomes profitable.

→ ROI (Return on Investment)

Identifies the year when cumulative savings offset the initial investment.

→ IRR (Internal Rate of Return)

Measures the overall performance of the project over time and makes it possible to compare solar with other financial investments.

This histogram, representing cash flows and the return on investment (ROI), allows to:

Visualize financial movements over a specified period, distinguishing between positive bars (income) and negative bars (expenses).
Identify the point where ROI becomes positive, indicating the recovery of the initial investment.
Track the evolution of net gains to evaluate the long-term profitability of the project. It is a clear tool for understanding financial performance and a decision-making aid for investors.

A stacked histogram comparing self-consumption savings to the public grid bill allows to:

Visualize the proportion of self-consumed energy that contributes to reducing the total bill (indicated at the bottom of each bar).
Illustrate dependency on the public grid (upper part of the bars) and identify the moments when it is at its maximum.
Facilitate the analysis of savings achieved through the solar installation as well as the periods during which an improvement (such as adding batteries) could lead to reduced grid-related costs.
This is an essential chart to demonstrate the financial benefits of a solar system in simple self-consumption.

This stacked histogram illustrates the distribution between self-consumption (in green) and network bill (in blue) over 20 years. It is a simple visual tool to demonstrate the profitability and efficiency of a solar installation in the long term.

The calculation of a country's carbon footprint allows for:

Evaluating the total greenhouse gas (GHG) emissions generated by its activities, including industry, transportation, agriculture, and energy consumption.
Identifying the main sources of emissions to prioritize reduction efforts.
Taking into account factors such as the carbon footprint of imports and exports to gain a comprehensive overview.
It is an essential tool for monitoring progress toward climate goals and guiding public policies toward a sustainable transition.

The calculation of the carbon balance of a solar installation allows to:

Evaluate the emissions avoided through the production of renewable energy, compared to conventional supply via the grid (often based on fossil fuels).
Quantify the positive environmental impact, particularly in terms of tons of CO₂ saved throughout the system's lifespan.
Highlight that each kWh of self-consumed solar energy directly contributes to reducing the household's carbon footprint.
It is a tangible demonstration of the future solar energy producer's commitment to a more sustainable lifestyle.