I recently attended NCAT (NSW Tribunal) in regards to solar and credits. The power can be kept in the landlords name to claim the credits, and the tenant is responsible for all other charges (I.e usage, supply costs) but it is recommended that if you are going to do this you atleast give the tenants any discounts (Pay on time) that they would normally receive. I have several owners who will give back a % of the rebate for power going back into the grid (5% of the total amount) as this is not costing them anything and the tenants appreciate it and tend to pay the accounts on time and in full as well as take care of the property better.