How can I access numerical values of variables calculated with Solve?

Question

I am trying to calculate some thermodynamical cycles so I often use lists with equations. Here's a simple example:

list1 = {
     x + 2 y == z,
     z - 2 x == 3z,
     y - z == 5 x}

Solve[list1,{x,y,z}]

{{x -> 0, y -> 0, z -> 0}}

The problem appears when I want to use the calculated values of x,y,z later on to calculate some other parameters. Mathematica every time keeps returning x,y or z instead of its numerical value. Is that because the result of Solve is a nested list? Anyway, what should I do to have an access to these values?