  We make use of the EDELWEISS-III array of germanium bolometers to search for
electron interactions at the keV scale induced by phenomena beyond the Standard
Model. A 90% C.L. lower limit is set on the electron lifetime decaying to
invisibles, $\tau > 1.2\times 10^{24}$ years. We investigate the emission of
axions or axionlike particles (ALPs) by the Sun, constraining the coupling
parameters $g_{ae}<1.1\times 10^{-11}$ and $g_{ae}\times g_{aN}^{\rm eff} <
3.5\times 10^{-17}$ at 90% C.L. in the massless limit. We also directly search
for the absorption of bosonic dark matter particles that would constitute our
local galactic halo. Limits are placed on the couplings of ALPs or hidden
photon dark matter in the mass range $0.8 - 500$ keV/c$^2$. Prospects for
searching for dark matter particles with masses down to 150 eV/c$^2$ using
improved detectors are presented.
