Yes, 20 kV is not much, but also 400 kV can be underground. What I meant is that even with such low voltage as 20 kV and even in countryside it may be worth it

Yes, 20 kV is not much, but also 400 kV can be underground. What I meant is that even with such low voltage as 20 kV and even in countryside it may be worth it to bury the cable.