  The H.E.S.S. collaboration recently reported the discovery of VHE gamma-ray
emission coincident with the young stellar cluster Westerlund 2. This system is
known to host a population of hot, massive stars, and, most particularly, the
WR binary WR20a. Particle acceleration to TeV energies in Westerlund 2 can be
accomplished in several alternative scenarios, therefore we only discuss
energetic constraints based on the total available kinetic energy in the
system, the actual mass loss rates of respective cluster members, and implied
gamma-ray production from processes such as inverse Compton scattering or
neutral pion decay. From the inferred gamma-ray luminosity of the order of
10^35 erg/s, implications for the efficiency of converting available kinetic
energy into non-thermal radiation associated with stellar winds in the
Westerlund 2 cluster are discussed under consideration of either the presence
or absence of wind clumping.
