Until now, supplying power without a grid connection has been costly

Places that are located far away from the grid, such as mountain huts, have until now needed a diesel generator or CHP plant to produce power. While the cost of purchasing such equipment may not be high, these systems are expensive to maintain and operate. Thanks to the hugely successful progress made in modern battery storage systems, regenerative power generators such as small wind power or photovoltaic systems not only offer a more environmentally friendly alternative, but also a more economically efficient one.

Battery storage systems provide green power

While renewable power generators are often the lowest-cost alternative to diesel and CHP plants, they do have one major disadvantage: if there is no wind, or during darkness, wind power and solar generators are unable to provide electricity. This is where battery storage systems offer a simple solution. If more power is produced than is needed, it is stored in the battery. As soon as more power is required than can be provided by the wind and sun, the storage system goes into operation and provides continuous power.

From now on, greener also means more economically efficient

Until just a few years ago, power from battery storage systems was very expensive, since the widely used lead-acid or lead-gel storage systems were subject to wear after only a few years of use, and had to be replaced. In recent years, lithium-ion technology has undergone rapid development and has become cost-effective thanks to increasing production quantities.

However, anyone who assumes that cheap storage systems are the most cost-efficient might be in for an unpleasant surprise – and not only with regard to safety. The lowest power storage costs are mainly achieved as a result of the longest possible service life of the battery storage system. However, this requires high-quality components and battery management that protects the cells.

Thanks to the latest cell technology and active battery control, TESVOLT storage systems are among those with the longest service life, making them highly economically efficient.

For this reason, the cost of generating power through a photovoltaic system in combination with a TESVOLT storage system are usually significantly lower than with a traditional diesel generator.

Replace or optimise – TESVOLT storage systems help reduce costs

With a battery storage system, it is frequently possible to supply power off grid with 100% renewable energy sources.

Even if the power supply from a photovoltaic and wind power system is not enough, or if an existing system is still too new to be replaced, a TESVOLT battery storage system can still reduce your electricity costs on an ongoing basis.

For example, in combination with a diesel generator, the storage system helps reduce the number of inefficient starts, and therefore also the cold running time of the generator, to a minimum. The power storage system extends the uninterrupted operating times of the generator, thus reducing the amount of fuel required, as well as the degree of wear and maintenance.

If regenerative power generators are also used, the electricity first comes from the storage system when there is no wind or in darkness. The generator only starts up when the storage system is empty. In this way, the operating hours of the diesel generator are reduced and the share of usable solar and wind power is increased.

What you should always look out for when buying a power storage system:

  • Fast charging capability (1C)
    This is essential for use at fast charging stations; otherwise, you will require an enormous, and therefore very costly, storage system in order to provide the necessary charging power within a short period of time. 1C means that a storage system can be fully charged or discharged within the space of an hour. In other words, a 1C 60 kWh storage system has a charging/discharging capacity of 60 kW. If the storage system has only 0.5C, you already need a 120 kWh storage system in order to be able to guarantee a 60 kW charging capacity.

  • High efficiency
    For every charging and discharging procedure, a portion of the energy is lost as a result of physical processes. The degree of system efficiency indicates how much of the energy that is fed into the storage system can in fact be removed again. This value should be above 95%. Then there are also losses incurred during standstill, for example as a result of the energy consumed by the control system. Outstanding quality systems have an own consumption of less than 5 watts when not in use.

  • Expansion and replacement
    For most systems, cells and batteries can be replaced or added within just a few months after commissioning, depending on the way the system is built. It is therefore advisable to choose a system that can still be expanded years later, or for which the battery cells can be replaced if maintenance is required.

  • The highest safety standards
    When choosing battery cells, make sure that they come from a safe origin and that they meet the highest quality standards. Well-known manufacturers offer premium quality cells, which are not flammable even when punctured with a metal pin. Monitoring the battery at the cell level also helps detect the need for maintenance at an early stage.

  • High cycle stability
    Battery storage systems wear down with each charging cycle. For this reason, a number of full charging cycles is indicated that the storage system is guaranteed to complete before it falls below a residual capacity level. For example, TESVOLT storage systems have a life expectancy of 6,000 cycles at a capacity of 70% (EOL – End-of-Life) at 1C charging/discharging. This means that in 16 years’ time, the storage system will still retain 70% of its original capacity when it is fully charged and discharged once a day. This value should not be confused with the service life in calendar years, which shows the maximum service life in years, regardless of how the system is used (for example, TESVOLT storage systems are designed with a service life of 30 years).

  • Outdoor installation
    At the installation site of the storage system, size and weight play a role, as do humidity and other environmental factors. Modular systems are available that can also be installed in small rooms, or which can be transported to the installation site as individual parts. If there is no space to install the system in the building, it can also be set up outdoors – as long as the right model is selected, for example with a particularly robust housing or the right climate conditioning system.

Alpine cabin completely independent from the power grid – Austria Read more

Storage system: TS 40
Capacity/output: 77 kWh / 36 kW
System: off-grid with 16 kW PV system + CHP plant
Battery power inverter: SMA Sunny Island
Commercial field: tourism
Purpose of use: autonomy from the power grid
Special features: self-reliance thanks to PV, storage system and CHP plant
Country/region: Wieming, Tirol
Partner: StromVomDach Erl

Do you have any questions? We will be happy to give you advice

Do you have any questions, or are you interested in purchasing a TESVOLT storage system? You are welcome to contact us.