  Observations of galaxy clusters show radio emission extended over almost the
system scale, necessitating mechanisms for particle acceleration. Previous
models for acceleration such as diffusive shock acceleration and that due to
turbulence fall short in terms of efficiency. In this letter, we propose the
possibility of acceleration via magnetic reconnection. In particular, we invoke
the plasmoid instability which has been previously applied to understand
particle energization in high energy systems. Turbulence in galaxy clusters
lead to fluctuation dynamos that are known to generate magnetic fields
structures consisting of sharp reversals. These form natural sites of
reconnection. We perform Particle-In-Cell (PIC) simulations of the plasmoid
instability in collisionless and nonrelativistic plasmas. We show that the
resulting particle energy spectra have power law indices that are consistent
with that inferred from observations. Our estimates of the maximum achievable
Lorentz factor is about $10^5$ indicating that acceleration due magnetic
reconnection is a promising avenue for understanding the origin of nonthermal
emission in galaxy clusters.
