  Simulation of fermionic many-body systems on a quantum computer requires a
suitable encoding of fermionic degrees of freedom into qubits. Here we revisit
the Superfast Encoding introduced by Kitaev and one of the authors. This
encoding maps a target fermionic Hamiltonian with two-body interactions on a
graph of degree $d$ to a qubit simulator Hamiltonian composed of Pauli
operators of weight $O(d)$. A system of $m$ fermi modes gets mapped to
$n=O(md)$ qubits. We propose Generalized Superfast Encodings (GSE) which
require the same number of qubits as the original one but have more favorable
properties. First, we describe a GSE such that the corresponding quantum code
corrects any single-qubit error provided that the interaction graph has degree
$d\ge 6$. In contrast, we prove that the original Superfast Encoding lacks the
error correction property for $d\le 6$. Secondly, we describe a GSE that
reduces the Pauli weight of the simulator Hamiltonian from $O(d)$ to
$O(\log{d})$. The robustness against errors and a simplified structure of the
simulator Hamiltonian offered by GSEs can make simulation of fermionic systems
within the reach of near-term quantum devices. As an example, we apply the new
encoding to the fermionic Hubbard model on a 2D lattice.
