How much does the energy storage cost?
The new edition of the My Electricity 4.0 program provides for subsidies for heat and electricity storage facilities. You will be able to get as much as PLN 5,000 for a thermal energy storage, and PLN 7,500 for an electricity storage. Recruitment for the program starts on April 15 - more details here.
We would like to introduce you to what an electricity storage is, often called an energy bank, electricity storage, or ESS (Energy Storage System). What role does it play and, most importantly, how much does the energy storage cost?
Why have an energy storage at all?
Our customers who decide on an energy storage have specific needs that such a solution is to meet. We can distinguish two main needs:
- having an alternative (emergency) power source in case of a power outage
- the ability to balance energy in a daily cycle in cooperation with a photovoltaic installation.
We cannot consider the implementation of energy storage as an investment that will bring a real return on money. Profitability in terms of return on investment, unlike in the case of a photovoltaic installation, does not exist at the moment. Not only will the photovoltaic installation pay for itself in about 6 years, it will also bring pure profit for the next 15-20 years. Energy storage is a cost, just like a washing machine or dishwasher. Thanks to it, we have energy independence, intelligent energy management at home and many other functionalities, but it is not a thing that gives a tangible relief to the household budget.
How much does the energy storage cost?
The cost of the energy storage depends on many factors, below you will find a list of the most important ones, so that you have a real idea of what you need and how they affect the price:
Type of batteries – the most commonly used LiFePO4 (lithium-ion) will be the most expensive, because they have a high energy density, a very large number of work cycles (up to 6000 cycles), they can be safely discharged to 0% and they self-discharge slowly. A cheaper solution will be lead-acid or acid batteries with gel electrolyte, unfortunately they are not adapted to everyday discharge, they will withstand about 600 work cycles and they should not be discharged more than 50 %.
Battery capacity [kWh] – the higher the capacity, the longer we will be able to use the battery before it runs out. Everyone needs a different amount of energy to store. On average, a 5kWh storage should be enough for about 12 hours of operation with a loss of the power grid. The average price for one kWh on the market is PLN 3,000 gross.
Warehouse 1f or 3f – The energy storage is a combination of an inverter and batteries. Its price will depend largely on whether we need to power one selected phase (i.e. a guaranteed circuit) or we want to power the entire 3-phase home installation. In the case of the Victron solution, which is our favorite, it will be a choice between one inverter or three separate devices.
Photovoltaic inverter – If you already have a photovoltaic installation, maybe your inverter is already a hybrid inverter and is adapted to connect low or high voltage batteries to it. If so, that's very good news. The cost of the project for you is mainly the cost of batteries and assembly.
Cooperation with the PV installation – not every energy storage can be integrated with a photovoltaic installation. For a Victron system, you will need an additional solar charge controller module.
live monitoring – some systems have real-time monitoring with the possibility of interfering with the system, solving problems on an ongoing basis, changing settings, reconfiguring the system and making changes in work patterns. This is especially useful in critical systems where reliability is paramount.
Electric car charger – the possibility of integrating the energy storage system with the charger for an electric car. It is possible to charge an electric car only with surpluses from the photovoltaic installation.
Switching time – most energy storage systems have a switching time imperceptible to electronic devices (less than 20 milliseconds). Some, e.g. Huawei and his Luna2000 energy storage it has a time of 3s. This means that everything in the house will turn off first, and then the storage will work and start supplying energy.
Maximum power – Depending on the connected batteries, they have the ability to give a certain amount of instantaneous power. This is due to the parameter defined by the multiplicity of C or the C-rate. For example, with a factor of 1C, a battery with a capacity of 7 kWh can give 7 kW of continuous power and will discharge at this power in 1 hour.
What is the exemplary price of an energy storage then?
The energy storage must always be matched to specific needs. The cost of the cheapest energy bank, e.g. to maintain the operation of the circulation pump for the central heating boiler or the controller of the DHW circulation pump, which we implemented, cost about PLN 4,000 gross. The solution is based on a Victron uninterruptible power supply with a maximum power of 500W and one Victron 12V/60Ah gel battery.
The price of the system full option: a 3-phase Victron system with 20 kWh batteries with a solar charger, a warehouse charging system with only 1 phase present, the cost is already about PLN 80,000 gross.
The price range is really big. You should always first determine what the warehouse will be used for and what capacity we need - we encourage you to contact us, we will help you with a professional valuation and choosing a solution.
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