  A new lattice model is presented for correlated electrons on the unrestricted
$4^L$-dimensional electronic Hilbert space $\otimes_{n=1}^L{\bf C}^4$ (where
$L$ is the lattice length). It is a supersymmetric generalization of the
Hubbard model, but differs from the extended Hubbard model proposed by Essler,
Korepin and Schoutens. The supersymmetry algebra of the new model is
superalgebra $gl(2|1)$. The model contains one symmetry-preserving free real
parameter which is the Hubbard interaction parameter $U$, and has its origin
here in the one-parameter family of inequivalent typical 4-dimensional irreps
of $gl(2|1)$. On a one-dimensional lattice, the model is exactly solvable by
the Bethe ansatz.
