  We explore the potential of net-baryon, net-proton and net-charge kurtosis
measurements to investigate the properties of hot and dense matter created in
relativistic heavy-ion collisions. Contrary to calculations in a grand
canonical ensemble we explicitly take into account exact electric and baryon
charge conservation on an event-by-event basis. This drastically limits the
width of baryon fluctuations. A simple model to account for this is to assume a
grand-canonical distribution with a sharp cut-off at the tails. We present
baseline predictions of the energy dependence of the net-baryon, net-proton and
net-charge kurtosis for central ($b\leq 2.75$ fm) Pb+Pb/Au+Au collisions from
$E_{lab}=2A$ GeV to $\sqrt{s_{NN}}=200$ GeV from the UrQMD model. While the
net-charge kurtosis is compatible with values around zero, the net-baryon
number decreases to large negative values with decreasing beam energy. The
net-proton kurtosis becomes only slightly negative for low $\sqrt{s_{NN}}$.
