Delivering reliable 24×7 services is the primary objective of every large building for which an uninterrupted power supply is essential. Diesel generating (DG) sets are commonly used in developing countries for power backup for all critical infrastructure. Owing to increasing pollution levels, most cities are banning Diesel Generator sets. There are many alternatives to DG sets, such as gas turbines and hydrogen fuel cells. Still, due to technological maturity, reliability, safety, and efficiency, the best option presently is lithium-ion battery (LiB) based energy storage systems or BESS.
DG sets burn diesel and emits carbon dioxide, carbon monoxide, nitrogen oxides (NOx), and particulate matter (PM 2.5 and PM 10)) besides causing noise pollution. DG sets release harmful particles into the atmosphere and substantially reduce air quality in the neighbourhood. Every litre of fuel burned in a DG set crates 0.73 kg of pure carbon and 2.6 kg of carbon dioxide. Battery Energy Storage System (BESS) is a rechargeable battery system that stores energy from the electric grid or any renewable energy sources and returns that energy to the building when needed. The key components of a BESS are Lithium-ion Battery (LiB) and Battery Management Systems (BMS).https://www.aurovilleconsulting.com/battery-energy-storage-systems-as-an-alternative-to-diesel-generators-a-comparative-cost-analysis-for-tamil-nadu/
A lithium BESS can be charged from the grid or solar rooftop photovoltaic (RTPV) systems installed on the building. While a typical DG set operates during power outages a few hours a month, the lithium BESS connected to the grid can support the grid 24×7 by providing frequency and voltage support. It can be a great resource for renewable energy (RE) and electric vehicle (EV) integration with the electricity distribution grid.
With the present cost of diesel, one unit(kWh) of electricity produced from a DG Set in the range of Indian Rs. 25-30, whereas the cost of electricity from BESS will be less than half of that, even if Lithium BESS is charged with electricity bought from the grid at a commercial tariff of Indian Rs. 7-8.
Innovative business models can be introduced to replace DG sets with BESS, which would be the fastest route to create distributed energy storage systems for the grid to build flexibility, emerging as the key requirement for renewable energy integration with the grid.
At Su-vastika, we have installed Lithium BESS in homes, hospitals, hotels, petrol pumps and offices and established a list of successful running projects in India for the first time. Our experience of installing these systems was mind-boggling, as the results were beyond our imagination. The cost comparison was the major factor initially with the backup time calculations.
Everyone was susceptible to the period as the Diesel Generator can give back unlimited hours, and Lithium BESS has the limitation of the battery bank sizing, which can’t be very large as the cost is a big challenge. So, when we started making and installing these projects, we calculated two hours of backup for the sites. We realized customers were getting more than six hours of backup as the Load ran uninterruptedly. The Load of Air conditioners and any other machinery does not change during running time and is quite standard, less than the Load we estimated while designing the system. The first system we installed was at the home of one of the entrepreneurs using a 62KVA diesel generator, and we replaced this with a 40KVA lithium battery with one hour of backup. To our surprise, his system ran for more than 5 hours when he tried to run the Load he used in his ordinary life.
My next experience was at a hospital in Gurgaon, which ran diesel generators extensively. The Load had 34 air conditioners, one lift, and an X-ray machine, and the IVF lab had incubators, RI witnesses, micromanipulators, IVF workstations, Coda Air systems, etc. CT scan system and having a lot of computers having one Operation theatre for which the power was required uninterrupted when the operation was performed. Here, the DG of 125 KVA was installed, the diesel bill was around Rs 25k to 30k, and DG was installed on a rental basis. We replaced this DG with our 50 KVA Lithium Battery Energy Storage System, and the results were amazing. The general maintenance of equipment cost was very high as the equipment failure was very high on the running of the diesel generator. Now, after the successful running of the Lithium inverter with a battery bank, we have concluded that the running cost, along with the savings in the maintenance cost, has brought the system cost recovery in less than two years, and the backup time this system is giving is almost 4 hours on general running.
After the experience of this hospital, we realized that the solution for the hospitals is BESS and not the diesel generators, as the cost savings and convenience for the hospitals are not comparable. The life of the lithium battery is not less than seven years, which can be a big savings for the hospital, and the patient not being able to face any power interruptions in the hospital is a big deal.
My next experience was with the hospitality industry when we installed an 80-room hotel called Classic Diplomat in Mahipalpur in New Delhi. Initially, we installed one 100 KVA Lithium Inverter, replacing 125 KVA. Diesel Generator: They had 375KVA diesel generators installed in different sections of the hotel, and the owner was also not very sure of the lithium inverter working for such a large installation. Hence, we ran this 100 KVA for the first three months. The hotel staff realized the difference between the Generator and Lithium inverter-based BESS very clearly, as there was no switching happening on the BESS side, and starting the generator took 3 to 5 minutes to change over time. The hotel had general lighting, Air conditioners in the corridors, and a CCTV system installed, which used to be stopped as there was no lighting for 3 to 5 minutes so that anyone could do anything then. The room lights and TVs were shut down for 5 minutes, so the guests’ experience was unpleasant. There was a kitchen in the hotel with a big exhaust fan to vent out the kitchen’s pollution outside, but when the power was cut off, the kitchen lights alongside the fan being stopped was such a big event for the kitchen staff to handle. Another major challenge was the small cold room for keeping the vegetables and fresh fruits for guests’ consumption. When there was a power cut, the stuff went bad as the cold room temperature fell below the limits, and the timings of starting the DG and bringing the same temperature took time. After installing the Lithium inverter, the staff realized there was no change in room temperature as the cold room was working uninterruptedly during the power cuts. The coffee machines and other machines’ lights and air conditioning work uninterruptedly. Which was such a delight for the hotel staff and the guests staying in the hotel. They have one marriage hall which used to have power interruptions, and the people having marriage functions used to see the interruptions, and this was one of the major benefits the hotel has seen now.https://suvastika.com/green-revolution-in-indian-hospitality-first-hotel-to-run-on-lithium-battery/
Another milestone was created by installing the Lithium Battery Energy Storage System in the factory Sun Food Tech in Bhiwadi, which opened our eyes regarding savings, backup time, and space-saving while removing the pollution in the factory environment. This factory used to waste a lot of raw materials during the power cuts, and the savings are a major achievement.https://suvastika.com/delhi-ncr-factory-swaps-diesel-generator-for-cleaner-lithium-battery-bank/
Another experience was the petrol pump installation we did at the IOC pump in Gurgaon, Haryana, as this was an eye-opener in terms of benefits and cost savings in running costs. A major challenge faced by the pump owners is the power is cut, the filling of the petrol or diesel stops and the operators have to wait for the Diesel generator to start after 3 to 5 minutes, power is stored, and the customer line increases in case the power cut keep happening.https://www.solarenergyforever.in/en/this-energy-storage-system-will-replace-your-diesel-generator/
The Lithium BESS is the next big innovation to take the Diesel generators by storm.