Soaking Transformer

What is the technical reason for soaking transformer not less than 12 hours? I just google it and found this. Not sure is it correct or not. But that one sounds good and reasonable. 

"To remove all moisture and air trapped in insulating material and windings". 

Usage Based Maintenance

Usage Based Maintenance (UBM)
- changeouts carried out at pre-determined intervals of usage.

Sampling:

1. Lube oil
2. Engine oil
3. Compressor
4. Boiler feed pump
5. Brake pad
6. CarvTyres
7. which using counter etc

What is Solar Power?

Solar power - conversion of energy from sunlight to electricity. The solar power is using direct photovoltaic or concentrated solar power. 

Concentrated solar power - use mirrors and tracking system to focus large area of sunlight into a small beam.