Very critical
Lets understand India
#BESS tender (Standalone)
1. Sample study on 100 MW/200 MWH 12 years 2 cycle per day 132 KV connected
2. 2.5% degradation allowed so minimum dispatchable energy also reduced accordingly and same is mentioned in RFS document.
3. You have to procure initial capacity accommodating only 200 MWH+ Aux losses (BESS)+Aux loss Fixed+ Equipment efficiency losses+ SOC window
4. RFS document given facility minimum dispatch considering 2.5% degradation every year so need not think for augmentation in future.
5. Excel sheet showing required capacity in MWH=200 MWH divided by DOD x PCS eff x RTE is totally misleading
6. BESSD asked to show rated MWH during COD so he will ensure 100 MW/200 MWH on that day
7. As per design in Storlytics year wise required MWH considering 2.5% degradation and as per design in Storlytics software is shown in image,
8. It is observed that even after putting rated 200 MWH during COD, we are putting more in coming years which is not required as per agreement but rated capacity to showcase during COD. Think on it.
9. Now comes on equipment efficiency loss part and site fixed auxiliary other than MV trafo, DC block and PCS, Power Transformer, AC cables, and DC cables etc. These are AC in the control room of substation, area lighting, battery charging for control supply, Scada UPS etc which is maximum 200 KW.
10. In tender document assuming 15% system RTE (AC POI to POI including EHV line), it is stated that Discom will feed around 235 MWH so that in return 200 MWH can be received.
11. Now if we consider all efficiency losses and aux losses +fixed plant aux loss including PSS aux. It will be around 17%.
12. Considering above say BESSD to keep BESS size at least 12% higher (4%+8%) so (200 MWHx12%+200 MWH) around 225 MWH+ max 95% -min 5% SOC window=235 MWH
13. So total 235 MWH to be installed at site. If we see actual requirement considering degradation, what is use of 235 MWH while we require only 140 MWH at the 12 years.
Lets discuss it.