**8. Environmental impacts and future promising technologies for renewable storage**

Key environmental impacts include: lifetime energy efficiency, lifecycle greenhouse gas emissions, supply chain criticality, material intensity, recyclability, and environmental health and social impacts as and safety and human rights. Energy efficiency of the life cycle is important since high performance sustained over a long planned lifetime minimizes the criteria for technological uptake and the related impacts. Supply chain criticality recognizes not only the geological availability of essential commodities but also the possible supply chain vulnerabilities and threats associated with fiscal, technical, social, or geopolitical influences. Owing to the high usage of nonrenewable materials in main energy storage systems, content intensity is an important parameter. Battery storage systems typically have a higher material density relative to other technologies.

#### *Energy Storage Efficiency DOI: http://dx.doi.org/10.5772/intechopen.109851*

The recyclability of battery storage technologies has the capacity to minimize high material intensity by recycle, reuse, or remanufacturing. Poor recyclability highlights the need to implement innovative approaches to infrastructure and technologies [65].

Environmental health is significant as an adverse effect on habitats or human health. The supply chain will negate the benefits of moving into a green energy system. Since batteries are material-intensive technologies, they have the most important impacts. The effect varies depending on the location of extraction, manufacturing, and end-of-life due to variations in technologies, production pathways, and local environmental and social norms. The most important mining impacts in China include pollution and water and soil emissions from lead, graphite, and phosphate mining, both of which have severe health impacts. There are important human rights impacts associated with the resource market for lithium-ion batteries, in particular lithium and cobalt. Cobalt mining is mostly undertaken by artisanal and small-scale miners who work in precarious environments in handheld mines without adequate protective equipment and widespread child labor.

### **8.1 Storage and future**

Targets aimed at zero emissions are more difficult and costly than net-zero goals, which utilize negative emissions technology to achieve a 100% reduction. Pursuing a zero, rather than net-zero, aim for the energy system may result in high power costs, making the achievement of economy-wide net-zero emissions by 2050 more difficult.

Storage can help poor countries lower their power costs while also delivering local and global environmental advantages. Lower storage costs enhance both the savings in electricity and the environmental advantages.

For example, E-mobility as one of the possible solutions for energy storage in coming years seems realistic. E-mobility is expanding, and now we are seeing hybrid vehicles, e-bikes, scooters, and kick bikes on the streets. They will shortly be followed by more fuel cell vehicles running on hydrogen. The use of all these vehicles will be expanded beyond their planned use as means of transport to also provide energy storage: they will charge when renewable energy is available in the system and feed back into the micro-grid battery as required. Such vehicle-to-grid and vehicle-to-building systems will become more prevalent as regulatory barriers are eliminated. With compact storage with more secure solid-state batteries and hydrogen bottles, our phones will never run out of batteries again [66]. Emerging battery storage systems would reduce energy storage costs and boost new opportunities in the energy market. In the coming decades, we are anticipating new types of batteries, such as solid-state batteries, to increase the efficiency of airplanes, vehicles, or medical devices. The other alternatives are sulfur-based chemistries, as their continued development would ensure the appropriate use of renewable-grid installations or magnesium batteries, which may meet their maximum capacity and be ready for commercialization within the next 5 years [67].

We can utilize energy more efficiently and reduce carbon emissions by storing it. Energy storage capacity would need to expand from 140 GW in 2014 to 450 GW in 2050 to keep global warming below 2°. Currently, just 3–4% of the power generated by utilities worldwide is stored.

Conclusion? We still have a long and difficult road ahead of us.
