Mod_08_18 – TPAR Current drafting assumes QPAR > 0; As a parameter which states over what absolute volume of balancing market accepted bids/offers will we create the volume weighted average price, no need for it ever to be negative; But there is a mathematical possibility that if QPAR were to be a negative number then there could be more than one unique answer, for example with QNIV = 5 and QPAR = -6: (Clause 11) If -QPAR <= QNIV <= QPAR: - (-6) <= 5 <= 6, 6 <= 5 <= 6, false so “If” statement fails; (Clause 12) If QNIV > QPAR: 5 > -6, true so “If” statement passes; (Clause 13) If QNIV < - QPAR: 5 < - (-6), 5 < 6, true so “If” statement passes. While it is not expected to happen in reality, this modification is being proposed to ensure that is unambiguously understood to be the case and also to ensure compliance for certification purposes by making it explicit that QPAR > 0 is expected.