  In engineering, it is a common desire to couple existing simulation tools
together into one big system by passing information from subsystems as
parameters into the subsystems under influence. As executed at fixed time
points, this data exchange gives the global method a strong explicit component,
and as flows of conserved quantities are passed across subsystem boundaries, it
is not ensured that systemwide balances are fulfilled: the system is not solved
as one single equation system. These balance errors can accumulate and make
simulation results inaccurate. Use of higher-order extrapolation in exchanged
data can reduce this problem but cannot solve it. The remaining balance error
has been handled in past work with balance correction methods which compensate
these errors by adding corrections for the balances to the signal in next
coupling time step. Further past work combined smooth extrapolation of
exchanged data and balance correction. This gives rise to the problem that
establishing balance of one quantity a posteriori due to the time delay in
general cannot establish or even disturbs the balances of quantities that
depend on the exchanged quantities, usually energy. In this work, a method is
suggested which allows to choose the quantity that should be balanced to be
that energy, and to accurately balance it.
