def cost_rule(mod, project, point, period):
    """
    **Constraint Name**: DRNew_Cost_Constraint
    **Enforced Over**: m.DR_NEW_PTS*m.PERIODS

    For each segment on the piecewise linear curve, the cost variable is
    constrained to be equal to or larger than the calculated value on the
    curve. Depending on the cumulative build (*DRNew_Energy_Capacity_MWh*)
    only one segment is active at a time. The supply curve is assumed to be
    convex, i.e. costs increase at an increasing rate as you move up the
    curve.
    """
    return mod.DRNew_Cost[project, period] \
        >= mod.dr_new_supply_curve_slope[project, point] \
        * mod.DRNew_Energy_Capacity_MWh[project, period] \
        + mod.dr_new_supply_curve_intercept[project, point]