Challenges of energy storage: TES global prospects

Energy is the fundamental need for the development, modernization and economic growth of any nation in the industrial sector in particular, and in all sectors in general.

Therefore, the uninterrupted supply of energy is one of the greatest needs and challenges of the modern world. In this context, TES technology is positioning itself as a solution to the challenges of energy storage.

Currently, the energy supply highly depends on the fossil fuels that make the environment vulnerable inducing pollution in it. 

In order to establish a sustainable energy system and overcome the energy and environmental crisis caused by the utilization of fossil fuels, a new energy revolution is taking shape with electricity as the central form of energy.

Thermal energy storage as power source

As a flexible power source, energy storage can be widely implemented and applied in power generation, transmission, distribution and utilization and it is widely recognized as a technology that can help to manage intermittent renewable energies in the electrical grid and an option for the future.

Within the available energy storage systems, thermal energy storage is the most attractive one since the energy storage efficiency of the thermal storage system can reach 95%-97%, the cost is only about 1/30 of the large-scale battery storage and their useful life is much longer.

Thermal energy storage (TES) systems are accumulators that store available thermal energy to be used in a later stage. These systems can store the thermal energy during the periods of excess of production and use it during the periods of high thermal energy needs, equalizing the production and the consumption of thermal energy and shaving the energy demand peaks. To sum up, TES is proving itself a key tool to face the challenges of energy storage.

This allows a decoupling between production and demand and therefore a reduction of the required capacity of the cooling and heating plants, because they can be designed not for the peak cooling demand but for the average demand, reducing the required capacity.

Thermal storage technologies are categorized into Heat storage systems and Cold storage systems. 

Cold Thermal Energy Storage Systems:

Cold storage systems are used worldwide and mostly use water as the storage medium due to its high specific heat and its accessibility.

Cold energy can be stored in water as sensible heat, lowering its temperature, and as latent heat, freezing it. In this way, two types of cold storage tanks are differentiated:

• Ice thermal storage tanks that use the latent heat of fusion of water to store cooling 
• Water thermal storage tanks that use the sensible heat capacity of water

Because latent heat of fusion of water is much higher than its sensible heat, ice storage tanks have greater energy storage densities compared to the stratified water storage tanks, but on the other hand they achieve lower efficiencies and require expensive additional equipment like glycol circuits. 

Due to the aforementioned advantages of stratified water thermal energy storage, they are the preferred solution in most of the Greenfield Central Cooling plants. More than 80% of the new District Cooling Plants in Dubai, Abu Dhabi, Saudi Arabia, Kuwait, Oman, Qatar, Jordan and other countries in the Middle East are designed with stratified water tanks.

Hot Thermal Energy Storage Systems

The transition towards climate neutrality has led to an increase in decarbonisation strategies. These strategies are strongly linked to the use of District Heating Systems with Thermal Storage Technologies. As we have already mentioned, the TES tank reduces operating cost and required capacity of district heating, increasing the efficiency of the heating plant and reducing the cost of capital.

In these cases, heat storage technologies focus on sensitive heat storage increasing the temperature of the heat storage material, generally water due to the same reasons as in Cold Storage Systems.

With the current trend of district heatings, the tanks that are usually used are atmospheric tanks up to 95ºC.

3 Challenges to beat in energy storage

Although the energy transition is in full swing, energy storage challenges remain unmet and technology is advancing more slowly in this field. 

Where energy generation from renewable sources is growing, energy storage is not keeping pace. But what is the point of generating energy cheaply when we cannot store it for use at peak demand?

In the 21st century, we still face some challenges in terms of batteries and storage that we need to address in the coming years if the energy transition is to be effective as soon as possible. 

1. High cost of implementation. Even though costs have been dropping in the last decade, batteries still require a high investment for many companies. That is why in ARANER we combine Thermal Energy Storage with efficient District Cooling and Heating systems, to reduce initial investment and create an efficient energy system for any plant.
2. Lack of standardization in storage systems. In the absence of effective standardisation, each manufacturer creates its own batteries. This often creates a challenge for projects that evolve over time as storage systems do not always fit the needs of the project and sometimes batteries need to be replaced. At ARANER we work to ensure that the systems are scalable and easy to expand, not just efficient in their initial conception.
3. Outdated regulatory policy and market design. As is the case whenever a new technology emerges, regulation is not always updated until it has become established and has evidenced a serious need for regulation. With energy storage we face this challenge. Although it is somewhat regulated at the industrial level, we do not expect to see clear regulation until batteries fully enter the residential market.

These are just the tip of the iceberg, but energy storage is presenting many more challenges that companies and businesses will have to deal with in the next few years to completely commit to energy transition and energy efficiency. Are you ready to start today? Contact ARANER to know more on how to implement and face the challenges of energy storage with District Energy Systems.