Installing solar panels to reduce your electricity bill is an increasingly popular approach. However, several methods exist. This article focuses on self-consumption without injection, a method that aims to consume all the electricity produced by your panels, without sending it back to the grid. We will explore the principles, benefits, procedures, and practical aspects of this solution.

Key takeaways on self-consumption without injection

• Self-consumption without injection involves using all the electricity produced by your solar panels, without re-injecting it into the public grid, even for free.
• Key benefits include a significant reduction in your electricity bill and a contribution to the use of renewable energies.
• To achieve this, several methods are possible: consuming all production, using a battery to store the surplus, or limiting the installation’s power via curtailment.
• Administrative procedures are important, notably signing a Self-Consumption Without Injection Agreement (CACSI) with the grid operator, and obtaining the necessary authorisations.
• This type of installation is generally not eligible for government aid, and the cost can be increased by storage solutions or specific equipment curtailment.

Understanding the principle of self-consumption without injection

Self-consumption without injection, also known as total self-consumption, is an approach aimed at consuming all the electricity produced by your photovoltaic installation, without re-injecting it into the public grid. This means that all the energy your solar panels generate is directly used by your household. It’s an approach gaining popularity, particularly with rising energy costs and increased environmental awareness.

Specifically, it involves producing your own electricity using solar panels and consuming it immediately. The goal is to achieve energy self-sufficiency as much as possible. Unlike other models, here, surplus production is neither sold nor even re-injected free of charge into the grid. It is either consumed or managed otherwise to prevent any injection.

The main distinction lies in the management of surplus production. In the case of self-consumption with resale, electricity not consumed immediately is sold to an energy distributor, often via a purchase agreement. This allows for generating additional income. Self-consumption without injection, however, focuses solely on direct consumption. There is no resale contract, which simplifies administrative procedures. Moreover, the procedures for self-consumption without injection are generally simpler, as they avoid the complexity of resale contracts self-consumption without injection.

In a self-consumption system without injection, surplus management is paramount. Several strategies can be implemented to avoid re-injecting it into the grid:

• Direct Consumption: Adjusting consumption habits to use electricity when it is produced (for example, running energy-intensive appliances during the day).
• Storage: Using solar batteries to store excess energy and reuse it later, particularly in the evening or on cloudy days.
• Curtailment: Limiting the maximum production power of the installation so that it never exceeds the household’s consumption capacity at any given moment.

The goal is to best match solar production with the household’s energy needs, in order to maximise self-consumption and minimise, or even eliminate, any injection into the grid.

The advantages of self-consumption without injection

Choosing self-consumption without injection means opting for an approach that offers several interesting benefits for your home or business. Beyond simply reducing your energy expenses, this approach is part of a broader vision for managing your consumption and environmental impact.

Significant reduction in electricity bill

One of the most immediate and tangible benefits of self-consumption without injection is the notable reduction in your electricity bill. By directly consuming the energy you produce with your solar panels, you reduce the amount of electricity you need to buy from your supplier. This translates into concrete savings, month after month. The more electricity you manage to consume on-site, the lower your bill. This approach helps to smooth out your energy costs in the long term, making you less susceptible to market price fluctuations. It’s a smart way to manage your energy budget.

Contribution to energy transition

By producing your own electricity from the sun, you actively participate in the energy transition. Solar energy is a renewable, clean energy that does not generate greenhouse gases during its production. By favouring this local and decarbonised energy source, you contribute to reducing dependence on fossil fuels and lowering the overall carbon footprint. It’s a concrete action for the environment, aligning with sustainable development goals. Every kilowatt-hour self-consumed is a kilowatt-hour that doesn’t need to be produced by thermal or nuclear power plants. It’s a way to act for a greener future, starting with your own consumption. The use of technologies like organic solar panels, which have a very short energy payback period, further reinforces this ecological aspect [dfbd].

Strengthening energy independence

Self-consumption without injection offers you an increased degree of energy independence. By producing part, or even all, of your electricity consumption, you become less dependent on the public grid and energy suppliers. This autonomy is particularly valuable in a context of volatile electricity prices. It allows you to better anticipate your expenses and protect yourself against unforeseen tariff increases. In the long term, this independence can translate into greater peace of mind in managing your energy. It’s an approach that makes you an active participant in your energy supply, giving you more control over your consumption and costs. Collective self-consumption, for example, allows this independence to be shared among several stakeholders [87a9].

Methods for achieving self-consumption without injection

To implement self-consumption without injection, several technical approaches ensure that all electricity produced is consumed on-site, without being re-injected into the public grid. The objective is to maximise the use of your own solar production.

Total consumption of produced electricity

The most direct method involves adjusting your consumption to perfectly match the production of your solar panels. This requires careful planning of electrical appliance usage. Ideally, your electricity needs should coincide with periods of strong sunshine. For example, scheduling the operation of large appliances like washing machines, dishwashers, or pool pumps during the hours when your panels produce the most energy. This demands some flexibility in your daily habits. If your panels produce more than you consume at any given moment, you end up with a surplus that, in this model, cannot be injected. It is therefore preferable to size the installation according to your actual consumption and habits to minimise this surplus. A good analysis of your electricity bills and the use of a smart meter like Linky can help to better understand these needs. To learn more about the administrative procedures related to self-consumption, you can consult the information on the signing of the self-consumption without injection agreement (CACSI).

Using a solar battery for storage

Another effective strategy for managing self-consumption without injection is the installation of a solar battery. This system allows excess electricity produced during the day, when consumption is low, to be stored for later use, for example in the evening or at night, when the panels are no longer producing. This significantly increases your self-consumption rate and reduces your reliance on the grid. The battery’s sizing must be adapted to both your panel production and your deferred consumption needs. Although the initial investment is more substantial, it offers greater energy autonomy.

Inverter curtailment

Inverter curtailment is a technical method that involves limiting the maximum power your photovoltaic installation can inject. In the context of self-consumption without injection, this can be used to ensure that production does not exceed a certain threshold, often linked to regulatory constraints or to prevent re-injection. For example, if regulations impose a power limit to avoid signing certain contracts or to simplify procedures, inverter curtailment is a solution. It is important to note that this method can lead to a potential loss of energy if production exceeds the set limit, even if this energy could be consumed. It is therefore essential to fully understand the implications of this limitation. For a comprehensive overview of the different self-consumption options, this guide on solar self-consumption may be useful.

Self-consumption without injection aims to consume all the energy you produce. This involves careful management of your consumption and, potentially, the addition of storage or power limitation solutions to prevent any re-injection into the public grid. It’s an approach that strengthens your energy independence and your contribution to renewable energies.

These different methods can be combined to optimise your self-consumption system without injection. The choice will depend on your budget, your consumption habits, and the specifics of your installation. The main objective remains to maximise the use of the solar energy you produce yourself, thereby contributing to better consumption management and a more ecological approach. Self-consumption is an excellent way to manage your energy more efficiently.

Administrative procedures for self-consumption without injection

Implementing a self-consumption without injection installation involves following a precise administrative process. It’s not just about installing panels and consuming the electricity produced; several steps are necessary to ensure everything is in order and secure. These procedures guarantee that your installation complies with current standards and that your situation is clearly defined with the grid operator.

Signing the self-consumption without injection agreement (CACSI)

The first and one of the most important steps is signing the Self-Consumption Without Injection Agreement (CACSI). This document is a formal agreement between you, as an electricity producer and consumer, and the distribution grid operator (generally Enedis in France). It formalises your commitment not to re-inject surplus production into the public grid. This agreement is mandatory for any self-consumption without injection installation. It specifies the technical and contractual terms of your connection and consumption. Without this signature, your installation will not be considered compliant.

Planning permissions and grid connection

Even before considering signing the CACSI, you must ensure you have the necessary authorisations. Depending on the nature and size of your installation, a prior declaration of works to your local council may be required. For larger installations, a building permit might even be necessary. In parallel, a grid connection request must be submitted to Enedis. This process ensures that your installation can be connected safely and that the technical conditions are met. This step can take time, so it is advisable to plan ahead. You can consult the general connection conditions on the Enedis website.

Obtaining the Consuel certificate

Once your installation is completed and connected, a final check is required: obtaining the Consuel certificate. Consuel (National Committee for the Safety of Electricity Users) is an independent body that issues a certificate of conformity for your electrical installation. This document proves that your system has been installed in compliance with current safety standards. It is essential to validate your installation and to officially commission it. Without this certificate, your installation could be considered non-compliant and pose risks to the safety of people and property. It is a guarantee of quality and safety for your self-consumption without injection project, allowing you to fully enjoy your solar energy production with complete peace of mind. This process is a key step to secure your installation.

Here is a summary of the main procedures:

• Signing the Self-Consumption Without Injection Agreement (CACSI) with the grid operator.
• Obtaining the necessary planning permissions (prior declaration or building permit).
• Submitting a grid connection request to Enedis.
• Installation by a qualified professional.
• Requesting and obtaining the Consuel certificate to attest to conformity.

Cost and investment analysis

Investing in a photovoltaic installation for self-consumption without injection represents a significant financial commitment. It is therefore crucial to fully understand the different expenditure items to assess the economic relevance of your project.

Initial cost of the photovoltaic installation

The budget to plan for the installation of solar panels depends on several factors, including the desired total power (expressed in kilowatt-peak, kWp) and the quality of the chosen equipment. The main elements to consider are:

• Solar panels: Their price varies according to technology (monocrystalline, polycrystalline), brand, and unit power.
• The inverter: Essential for converting the direct current produced by the panels into alternating current usable by your appliances. Its cost depends on its power and features.
• The mounting system: Adapted to your roof type (tiles, slates, steel deck) or for a ground-mounted installation.
• Installation and fitting: Labour costs by qualified professionals.

It is important to note that the price of solar panels has significantly decreased in recent years, making the investment more accessible. For a modest power installation, typical of a self-consumption without injection approach, the cost can fall within a reasonable range, but it remains a substantial initial investment.

Financial impact of storage or curtailment

To maximise your self-consumption without injection, two main options are available to manage surplus production: battery storage or inverter curtailment.

• Battery storage: Adding a battery allows excess electricity produced during the day to be stored for use in the evening or on cloudy days. This solution increases the self-consumption rate but represents a significant additional cost, often in the order of several thousand euros. The increased energy autonomy justifies this investment for some households.
• Inverter curtailment: This method involves limiting the production of your solar panels so that it closely matches your instantaneous consumption, thus avoiding producing a surplus that could neither be consumed nor stored. Curtailment is generally an integrated option in the inverter and does not incur major additional costs, but it can limit the overall production potential of your installation.

Absence of government aid for this type of installation

An important point to highlight regarding self-consumption without injection is the absence of direct government financial aid for this specific model. Unlike installations with surplus resale, which can benefit from guaranteed purchase tariffs or premiums, total self-consumption without resale is not subject to public subsidies. This means that the entire cost of the installation, including any storage devices, relies on your personal investment. Profitability therefore depends solely on the savings made on your electricity bill. It is therefore even more important to correctly size your installation and analyse your consumption habits to optimise the return on investment. Buying electricity remains significantly more expensive than selling surplus, which makes consuming your own production particularly attractive. For example, the purchase price of electricity from the grid can be 20.62 euro cents per kWh, while the resale tariff for surplus is much lower. Comparing solar solutions can help you better understand these costs.

Optimising your installation for self-consumption without injection

For your self-consumption without injection project to be a success, you need to carefully adjust your system to your habits. It’s not just a matter of installing panels and hoping for the best; a thoughtful approach is required.

Sizing adapted to consumption

The first, and perhaps most important, step is to ensure that the power of your photovoltaic installation matches your actual needs. Too powerful, and you risk producing more than you can consume or store, which, in the case of self-consumption without injection, means the surplus is lost. Too weak, and you won’t fully benefit from solar energy. You need to find the right balance. Precise sizing is key to maximising your savings.

Analysis of consumption habits

It is essential to understand when and how you consume your electricity. If your peak consumption coincides with daylight hours, self-consumption will be more efficient. If, on the contrary, you mainly consume in the evening, storage solutions will need to be considered. Observing your lifestyle will help you adapt your installation. For example, if you work from home, your daytime consumption will be higher, which is ideal for solar self-consumption.

Importance of electricity bills and the Linky meter

Your past electricity bills are a wealth of information. They indicate your average annual consumption in kilowatt-hours (kWh). The Linky meter, in particular, provides detailed data on your hourly consumption, which is extremely useful for refining the sizing of your system. This data allows for better anticipation of necessary production and avoids costly oversizing. A thorough analysis of these elements will enable you to build a solar project adapted to your energy usage.

Optimisation doesn’t stop at the initial installation. It’s a continuous process of adjusting and understanding your system and energy needs.

Technical constraints of self-consumption without injection

Even if the idea of consuming all your solar energy without re-injecting it into the public grid may seem simple, several technical challenges deserve consideration. These constraints can affect the performance and profitability of your installation.

Mismatch between solar production and consumption needs

The sun doesn’t always shine when we need electricity. Solar production is maximal in the middle of the day, often when most households are not very busy. Electricity needs, however, are greater in the morning and evening. This time lag is the main difficulty. Without a storage system or the possibility of re-injecting the surplus, electricity produced in too large a quantity during the day cannot be used later, once the sun has set. It is therefore necessary to find ways to best align production and consumption, which is not always straightforward.

Dependence on weather conditions

Like any photovoltaic installation, self-consumption without injection is directly influenced by the weather. A cloudy sky, rain, or even a simple autumn day with less sunshine will reduce the amount of electricity produced. If your system is sized to cover the majority of your needs on sunny days, a prolonged period of bad weather may force you to draw more from the public grid, cancelling out some of the expected benefits. It is therefore important not to overestimate the average annual production.

Limitations in case of insufficient production

If your installation does not produce enough electricity to cover your needs, you will be obliged to purchase the supplement from your energy supplier. This can happen at night, on very cloudy days, or if your system is undersized compared to your actual consumption. In the context of self-consumption without injection, there is no possibility of reselling the surplus to offset these purchases. It is therefore necessary to ensure that the sizing of the installation, combined with a good analysis of your consumption habits, minimises these situations. The use of a virtual photovoltaic storage solution can help to better manage these variations without investing in physical batteries.

It is imperative to understand that self-consumption without injection requires active consumption management to maximise the use of produced solar energy. This often involves adjustments in daily habits to match consumption peaks with periods of high solar production. Compliance with standards, such as the update to standard NF C15-100 which will come into force on 1 September 2025, is also a technical point not to be overlooked for the safety of your installation [b26c].

Here are a few points to keep in mind:

• Precise sizing: A thorough study of your consumption is necessary to avoid both oversizing (costly) and undersizing (inefficient).
• Surplus management: Without the possibility of re-injection, you must either consume immediately or store. Inverter curtailment is a method to limit production, but it is not always the most economical.
• Evolving needs: Your electricity needs may change over time (arrival of a new electric vehicle, change of household appliances). Your installation must be able to adapt or be re-evaluated.

Signing the self-consumption without injection agreement (CACSI) with the grid operator, such as Enedis, is a key step that formalises the power limits not to be exceeded to avoid injection into the grid [1948].

The role of the grid operator in self-consumption without injection

The grid operator, often Enedis in France, plays a key role in the establishment and proper functioning of your self-consumption without injection installation. It’s not just about installing panels and switching them on; there are rules to follow to ensure everything runs smoothly and safely. It is the operator who ensures that your installation complies with standards and does not impact the stability of the general electricity grid. Without their validation, your project cannot proceed.

Agreement obligation

To be able to consume your own solar electricity without re-injecting it into the grid, an administrative step is mandatory: signing an agreement. This is the Self-Consumption Without Injection Agreement (CACSI). This document formalises your commitment not to inject surplus production into the public grid. It’s a type of contract between you and the grid operator that governs this specific practice. It is important to fully understand the terms of this agreement before signing it, as it defines the modalities of your installation in relation to the grid. This step is essential to ensure the compliance of your project.

Importance of grid connection

Even if you don’t re-inject your surplus, your installation must be connected to the public grid. Why? Because the grid acts as a safety net. If your panels produce less than you need at any given moment, the grid takes over to fill the gap. Conversely, if you produce more than you consume instantaneously (and you don’t have a battery), the surplus, although not injected, must be managed. The connection therefore allows for a continuous and reliable electricity supply for your home. It guarantees that you always have electricity, regardless of your solar panels’ production at any given moment.

Compliance with electrical standards

The grid operator ensures that your installation complies with current electrical standards. This concerns the quality of the equipment used, the safety of the electrical installation, and how it is connected to the grid. The objective is twofold: to protect your installation against surges or other electrical problems, and above all, to guarantee the safety of technicians who might work on the grid and its stability. Obtaining the Consuel certificate of conformity is often a step requested by the grid operator to attest that everything is in order before your system is commissioned. This is a guarantee that your installation is safe and well-executed, which is fundamental for successful self-consumption.

Comparison with other self-consumption models

Self-consumption without injection represents a specific approach to solar energy production. It is useful to compare it with other models to fully grasp its particularities and advantages.

Self-consumption with surplus resale

This model is undoubtedly the most well-known. Here, the electricity you produce and consume directly is self-consumption. However, anything you don’t consume immediately, the famous surplus, is injected into the public grid. This surplus is then paid for at a purchase tariff set by law. This is a way to make part of your installation profitable through the sale of excess energy. The main advantage is therefore twofold: a reduction in your electricity bill through direct consumption, and additional income through resale.

Total self-consumption without resale

This is the model we are discussing in this article. The objective is to consume all the electricity produced by your solar panels. There is no injection of surplus into the grid. If your production exceeds your consumption, the excess is neither sold nor injected. It is simply lost, unless you have implemented storage solutions such as batteries. This model aims for maximum energy independence, but it requires good management of production and consumption, often aided by intelligent control systems. The absence of resale means there is no additional income, but the bill reduction can be even more significant if the self-consumption rate is very high. It is important to correctly size your installation to avoid production losses. To optimise the use of solar energy, solutions such as dynamic power control can be considered.

Dual self-consumption (photovoltaic and thermal)

This model goes a little further by combining two types of renewable energy production. It involves using hybrid solar panels that produce both electricity (photovoltaic effect) and domestic hot water (thermal effect). The electricity produced is consumed locally, as in classic self-consumption. The hot water produced can be used for heating or domestic hot water. The advantage is a maximisation of energy savings, as you cover two essential needs of your household with a single technology. This helps to reduce both the electricity bill and the bill related to heating or hot water production, which often depends on other energy sources. This is a solution that requires a potentially higher initial investment but offers more comprehensive energy coverage.

Calculating the self-consumption rate

To accurately measure the efficiency of your solar installation in self-consumption without injection, it is important to understand and calculate your self-consumption rate. This figure gives you a precise idea of the proportion of electricity you produce yourself and consume directly, without having to re-inject it into the grid.

The calculation is quite simple and is based on two main elements: the quantity of electricity your solar panels produce and the quantity of this production that you consume on-site.

The general formula is as follows:

Self-consumption rate = (Solar production consumed on-site / Total solar production) * 100

For example, if your solar panels produced 10 kWh in a day and you consumed 8 kWh of that production directly in your home, your self-consumption rate for that day is (8 / 10) * 100 = 80%.

A high self-consumption rate means that you use a large proportion of the electricity you produce. This directly translates into a reduction in your dependence on the public grid and, consequently, a decrease in your electricity bill. A rate of 100% would be ideal, but it is often difficult to achieve in practice due to the discrepancies between solar production times and electricity consumption times.

It is important not to confuse the self-consumption rate with the self-production rate. The self-consumption rate measures the proportion of your solar production that you consume, while the self-production rate measures the proportion of your total consumption that is covered by your solar production.

The higher your self-consumption rate, the greater your savings on your electricity bill will be. Every kWh self-consumed is a kWh you don’t need to buy from the energy supplier. For example, if the price of a kWh purchased from the grid is €0.20, every kWh you self-consume saves you that amount.

To optimise this rate, several strategies can be implemented:

• Adapt your consumption habits: Try to run your energy-intensive appliances (washing machine, dishwasher, etc.) during daylight hours.
• Use a storage system: A solar battery allows you to store excess production for later use, for example in the evening or on less sunny days.
• Optimise the installation’s sizing: A system well-sized in relation to your actual consumption maximises self-consumption.

Regular monitoring of your self-consumption rate allows you to evaluate the performance of your installation and adjust your practices to maximise your gains.

Wondering how much of the electricity you produce you consume directly? That’s your self-consumption rate! Knowing how to calculate it helps you better understand your solar production. To find out how to do this calculation simply and optimise your installation, visit our website today!

To conclude: self-consumption without injection, an option to consider

So, we come to the end of our exploration of self-consumption without injection. As we have seen, this approach involves using all the electricity produced by your solar panels, without sending any surplus back to the public grid. It’s a direct way to reduce your electricity bill while contributing to the growth of renewable energies. However, it’s important to bear in mind that this may require some technical adjustments, such as curtailing your system or adding a storage battery, which represents an additional cost. Furthermore, administrative procedures, particularly signing the CACSI agreement, are mandatory. If you are considering this solution, a thorough analysis of your consumption and precise sizing of your installation are truly key to getting the most out of it. Don’t hesitate to seek advice from professionals to ensure your project perfectly matches your needs.

Frequently Asked Questions

What is self-consumption without injection?

Self-consumption without injection is when you use all the electricity your solar panels produce, without sending any surplus back to the public electricity grid. You consume your own solar energy directly.

What is the difference between self-consumption with and without injection?

With self-consumption with injection, you can either sell the unconsumed electricity surplus to the grid or re-inject it for free. In the case of self-consumption without injection, you can neither sell nor re-inject this surplus. It is either consumed, stored, or limited by curtailment.

Why choose self-consumption without injection?

The main reasons are to further reduce your electricity bill by using all your production, and to actively participate in the energy transition by consuming clean energy. It also strengthens your independence from energy suppliers.

How can I consume all my solar production without injection?

Several solutions exist. You can try to consume all the electricity produced during the day. Alternatively, you can use a solar battery to store surplus electricity and use it later, or curtail your system so that it doesn’t produce more than you consume.

What administrative procedures are necessary?

You must sign an agreement called CACSI (Self-Consumption Without Injection Agreement) with the grid operator. You also need to obtain the necessary authorisations for the installation and have the work verified by a body such as Consuel.

What is the cost of a self-consumption without injection installation?

The cost depends on the size of your solar installation. If you choose to store the surplus with a battery or curtail your system, this represents an additional cost. It is important to note that government aid is generally not available for this specific type of installation.

What are the technical constraints of self-consumption without injection?

The main challenge is that the sun doesn’t always shine when you need electricity (for example, at night or when it’s cloudy). You therefore need to adapt your consumption to production, or plan for storage. Production also depends heavily on the weather.

How do I know if my installation is correctly sized for self-consumption without injection?

To optimise your installation, it is crucial to size it correctly according to your consumption habits. Look at your old electricity bills or the data from your Linky meter to estimate how much electricity you use and when you use it most.