This is the build I have been using for a long time now, My friends love the Regeneration and Armour it gives them so figured I would share it on here.

This build is effectively min maxing the mods so that the drain isn't insane while at the same time being incredibly good.

Before you use renewal make sure you pick up an energy orb and put a status effect on an enemy (this can be seen in the top right). Once you have both of the buffs at the same time that is when you cast Renewal. Once renewal has been cast you can use Hallowed Ground to give the Armour buff.

If you have done it correctly you and your team should have a total of:
134 health regeneration a second.
670 Armour from Hallowed Ground

The energy cost will be:
38.75 for the actual cast of Renewal
77.50 for the cast of Hallowed Ground
2.14 energy Drain a second for Renewal
3.21 energy Drain a second per target needing health
(e.g. 2 teammates healing = 6.42 + 2.14 for general drain = 8.66/s)
Although this may seem like a lot if you are running low on energy just stand still and let the enemies shoot you to regain it from hunter Adrenalin.

If you were to replace your number 1 ability with the Helminth ability "empower" you could increase the Regen and Armour to 154 health/s and 770 armour. Just be sure to use it before Renewal.