The energy and computational constraints of Wireless Sensor Networks (WSN) have motivated the exploration of efficient routing algorithms. In this paper, a new routing approach is presented which attains the best trade-off between energy expenditure and hop-distance to the sink. The routing algorithm exploits a low-computation metric based on the node's remaining battery. Routing is performed by means of a modified Dijkstra's algorithm which calculates the node's position in the routing tree while computes the least-cost path of all nodes towards the sink. Simulations were performed for different network densities demonstrating that the proposed algorithm enhances the overall energy conservation of the network while efficiently routing data traffic.