1-tabling 100NL you get $7 an hour between raw winnings and rakeback, assuming a winrate of 5BB/100. Assuming a slightly higher winrate (say 7bb/100 or so) from the added skill edge of sitting on just one table (and then further assuming that you can in fact sit on one table and not get bored and play too many hands), that jumps to $8.50 an hour.
Really you need to 4-table at least to get enough volume to make real money
from cash tables. a 50NL winner can get about $12-ish an hour from four 6max tables, a 100NL reg can get maybe $20 or so (beating 100NL in multiple tables is MUCH tougher than beating 50NL, because most 100NL players are skilled lags so decisions against them are more complex).