actually add the api calls... oops

sparkapi/lua/energy.lua

@@ -0,0 +1,16 @@
+if not sparktech then sparktech = {} end
+
+function sparktech.can_drain_energy(target_pos, ammount) ---
+	--- check whether you can drain
+	return minetest.get_meta(target_pos):get_int("energy") >= ammount
+end
+
+function sparktech.drain_energy(target_pos, ammount)
+	local target = minetest.get_meta(target_pos)
+	local current = target:get_int("energy")
+	if sparktech.can_drain_energy(target_pos, ammount) then
+		target:set_int("energy", current - ammount)
+		return true
+	end
+	return false
+end