This mod will allow you to create smaller portals in Hell. Thus, it will be possible to use much less obsidian blocks and save it.
Smaller Nether Portals Mod for Minecraft 1.15.2/1.14.4/1.12.2
Smaller portals will work just like regular portals. Create small portals and navigate them to hell. In Hell, a regular sized portal will be generated.
1.15.2 – Smaller-Nether-Portals-Mod-1.15.2
1.14.4 – Smaller-Nether-Portals-Mod-1.14.4
1.12.2 – Smaller-Nether-Portals-Mod-1.12.2