New plants produce a lot less waste.
And the reason nuclear waste seems so expensive is because we have externalized the cost of most other forms of power generation. Coal and gas, well we just let people get sick or die.
Natural gas, fracking has huge negative impacts on communities, lots of illness, but again, we don't count that as part of the "financial cost" of natural gas.
Solar, we have the panels made in some other country, we have the raw materials mined in some other country, we import the final product, now it is clean energy.
(I support solar, but there is an environmental cost to solar panels!)
Nuclear makes us confront the waste up front, so now we are all freaked out about it.
As has been pointed out repeatedly, you could take a football field, dig down a few stories, and put all the nuclear waste needed for energy generation in there, and then have enough left over to keep storing spent fuel from new high efficiency reactors until sometime until well after everyone reading HN is dead and gone.
It is a crap shoot if the cost of paying the lawyers to deal with all the lawsuits over where to build the storage site will end up costing more or less than the storage itself.