The gas shortage is becoming terrible. I suggest that we should get rid of the conventional geysers and go for alternate.
Solar water heaters are very common in China ... and in Nepal, every roof top shows one solar water heater.

I just got this photo from an ad on and the seller has demanded Rs. 30K.
It is really a nightmare to use conventional geyser during gas shortage period in winter. In my area, the gas shortage persists till about midnight, so I had to get out in chilled weather to try and light up the geyser.
I think a practical solution is to have a solar water heater, and one 12 lit capacity low pressure instant water heater in each bathroom and also in the kitchen
I am planning to do it InshaAllah, when I start building my house this year