There is a classical connection between Riesz-potentials, Riesz-energies and Hausdorff dimension. Otto Frostman (Lund) proved in his thesis that if $E$ is a set and $\mu$ is a measure with support in $E$, then the Hausdorff dimension of $E$ is at least $s$ if the $s$-dimensional Riesz-energy of $\mu$ is finite. I will first recall Frostman’s result and some of its applications. I will then mention some new methods where Hausdorff dimension is calculated using potentials and energies with inhomogeneous kernels. Some applications are in stochastic geometry and dynamical systems.