The energy storage revolution is quiet, but it is already here

A rise in the number of energy storage systems

Energy storage systems have the potential to trigger massive growth in decentralized electricity generation. The steep decline in solar PV module prices over the past two decades has made solar PV systems more accessible to a wide range of consumers. Thus, the share of variable energy that is extracted from renewable energy sources continues to grow.

On the one hand, this contributes to the achievement of the pan-European goals of increasing the share of low-carbon electricity in the energy mix. On the other hand, it poses challenges to operators, as renewables produce variable energy, which makes balancing the energy system more difficult.

Increasing the number of electricity storage systems is the key to improving the flexibility and resilience of the energy system. It is also the basis that is needed to transform our transport system into one in which electric vehicles dominate.

A fall in the cost of batteries

Globally, the commercialization and diffusion of new battery technologies over the last decade has led to a rapid decline in their cost, especially for lithium-ion batteries. This decline is expected to continue with even greater force until 2030. The most significant decline is projected in the cost of lithium-ion (Li-ion) and flow-through batteries (Flow) (Figure 1).

Figure 1. Cost of the different energy storage technologies and decline by 2030 (IRENA, 2017)

The cost reduction is mainly driven by optimization of production bases, more efficient and environmentally friendly choice of materials used. The decline is expected to be accompanied by improved performance and longer battery life.

Battery storage and solar PV systems: the perfect match 

The productivity of solar PV systems, which is highest in the hours with the strongest sunshine, does not coincide with the hours of peak electricity consumption in an energy system (Figure 2). This is especially true for the evening peak (9-10pm), when the sun has already set and the solar PV panels have taken a break for the day.

Figure 2. Actual load (7 days) and forecasted load (7 days) in MW (ESO, 2021)

In this sense, rechargeable batteries are the ideal match for residential solar PV systems. They allow the energy produced by the system between noon and sunset to be stored and used in the evening when it is most needed.

Innovative energy storage solutions: Huawei Luna-2000

Lithium-ion batteries are one of the most important technological innovations of our time. In 2019 The Nobel Prize in Chemistry was awarded to John Goodenoff, Stanley Whittingham and Akira Yoshino for “the development of lithium-ion batteries.”

They have many advantages over other types of energy storage technologies, despite their relative “youth”. Their higher power density is the reason they are used as solutions in mobile phones and electric cars.

Their big advantage is that they do not require maintenance, unlike other types of rechargeable batteries. Lithium-ion batteries have very good characteristics that are favorable to the loads they supply. They provide a relatively constant voltage of 3.6V (per cell), and this voltage does not change drastically when the battery is completely discharged. The voltage drop between a fully charged battery and a discharged one is only 3 to 5%.

We found the perfect partner for residential solar PV systems in the new Huawei Luna-2000. 

Their modular system allows investment flexibility with the option to quickly and easily upgrade with several modules of 5kW each, up to a total capacity of 30kWh. In the case of a combination of several modules, in the event of a fault in one of them, it is automatically isolated to keep the entire system running.

Luna-2000 batteries have many other advantages. With dimensions of 670 x 150 x 600 mm and a weight of 63.8 kg, each 5kW module has a modern clean design. The batteries provide safe and reliable use with a lithium-iron-phosphate (LFP) cell. They provide 100% discharge depth (DoD) and more usable energy by optimizing energy at the system level.

This innovative series of high-voltage batteries is compatible with a wide range of inverters, but is particularly easy for installation, use and data monitoring in combination with Huawei SUN2000-2-6KTL-L1 series single-phase inverters and SUN2000 KTL-M0 series three-phase inverters and KTL-M1.

We are particularly excited about the possibility of integrating Luna-2000 with Huawei’s various home energy security solutions (Figure 4).