Like others have said,, the ones like we have on our motorhome provide little shade. But it is still better than nothing. We helped that out by adding a 2 ft drop down curtain that we can also hook another 6' drop down curtain to. We don't use it much but when we do it's great.
Of course we turn off the auto retract feature when we do this. And I do anchor the awning down lightly using a very small bunggie type rope that gives a little. And we alway retract the awning when we go away and at night.