AGE when its launched in 2019 will be specifically for part ownership and income from renewable energy assets. POWR is still required by application hosts to access the Power Ledger applications such as uGrid / xGrid p2p trading.
POWR holders will have the opportunity for priority access to AGE and discounts if they wish to participate. If you think you will be interested in this, once youve purchased your POWR on BTCmarkets you should move it to a private wallet so your POWR holdings can be verified for priority access to AGE