Regional defaults: EIA (US) and Ofgem (UK) update automatically; AER (AU) and MBIE (NZ) are checked periodically. Enter your own rate for a precise result.
Self-consumed solar saves the full import rate. Exported solar saves the feed-in tariff rate instead. Your NAS draws power continuously, it will consume solar whenever the sun is generating. Typical self-consumption for a 24/7 device: 30-50% in summer, 15-30% in winter.