// Update is called once per frame
 void FixedUpdate()
 {
     //2017-01-24: copied from WeightSwitchActivator.FixedUpdate()
     Collider2D[] hitColliders = Physics2D.OverlapCircleAll(transform.position, range);
     for (int i = 0; i < hitColliders.Length; i++)
     {
         GameObject hc = hitColliders[i].gameObject;
         if (!hc.Equals(gameObject))
         {
             PowerConduit pc = hc.GetComponent <PowerConduit>();
             if (pc != null && pc.convertsToEnergy)
             {
                 float amountTaken = pc.convertSourceToEnergy(energy, Time.fixedTime);
                 adjustEnergy(-amountTaken);
             }
         }
     }
     if (energy <= 0)
     {
         dissipate();
     }
 }