There is Not a Wind/Solar Power Grid In The World Without Fossil Fuel Backup!
The backup option could do what the RE monsters do and much better than that – but the RE monsters cannot do what the backup can do. This means that RE is about as useful as a nose right above your butthole. No RE enthusiast has ever responded to that question and also, as you need to factor the cost of the backup into the cost of RE and backup does not need RE, backup must necessarily always be cheaper. No matter what the backup is.