Governments must increase bioenergy use to realise the Paris agreement ambition. Most countries have limited biomass resources and policy goals beyond carbon reduction. This can lead to policy incoherence. Previous studies tended to focus on one end-use sector or on optimising CO2 reduction. This study goes beyond optimisation approaches and investigates cross sector impacts of bioenergy policy proposals via simulation methods for policy proposals in Ireland. As an EU member with ambition for increased bioenergy use, Ireland is a useful case to examine trade-offs. Using the BioHEAT policy decision support tool (Durusut et al., 2018) we find policy in the heat and transport sector close the gap to Ireland's 2030 climate targets by 3%. Policy supporting co-firing of biomass with fossil-fuel to produce electricity increases emissions by 8.3 MtCO(2) overall and reduces the policy impact on national climate targets by 63%. Co-firing uses more of the available biomass resources and this limits renewable uptake in the heat sector. Coal conversions and the use of advanced biofuels are found to rely on high availability of imports. Policy supporting biomass use in the power sector may make national climate targets less achievable for EU countries.