In this paper, we examined the fact that there is a correlation between the amount of accredited capacity installed via the Feed-in Tariff and the road network density at that region, and assumed that the high density of the road network can be indicative of the ease of civil engineering work. Using this method, we selected some prefectures with high renewable energy potential, and examined the relation between the potentials and the road network densities of the higher ranked municipalities among them. As a result, we found that there are several municipalities with high road network density, and potential distribution for small/medium-scale hydropower, PV power and wood biomass power. Since the potentials are scattered at points close to each other within municipalities in such areas, it is possible to share the common civil engineering work costs by simultaneously promoting development, thus reducing the construction costs. This method can serve as an index for selecting verification test sites to promote the dissemination of renewable energy by reducing construction costs. Going forward, however, the specific cost calculations will be required individually.