Our solar rank indicates the areas throughout the world that are most sunny and least sunny. However, while counterintuitive, some of the least sunny locations have the heaviest solar development and some of the sunniest areas are not necessarily the best locations for development. For solar renewable energy, there are numerous factors to consider when determining the viability of a project.

Government Incentives
One major factor to consider when investing in solar development is the type of government incentives offered at a location. These can play a highly influential role in funding a project, making it more affordable to build, and reducing the amount of time it takes to recoup the cost of the system.

For example, Seatte, WA, the location of 3TIER’s global headquarters, has a solar rank of 18% and Berlin, Germany has a rank of 10%. While Seattle’s resource rank is higher, Berlin has over 8,000 installed solar projects and Seattle has less than 200. The difference in the number projects is due to government incentives established in Germany in 2000 for solar installations, which have greatly assisted Germany in building an extensive network of solar power projects.

Considering Available Resources
Another important question is: are other resources available nearby? Looking at the wind rank for a potential solar energy site is important because high winds can cause vibration in equipment and reduce efficiency. At the same time moderate winds are helpful for preventing equipment from overheating.

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It is also useful to look at the hydro rank for a solar site. Solar photovoltaic panels must be kept clean and free of objects and particles, such as dust, that interfere with sun capture. This means a nearby water source is necessary for washing off the panels and that some amount of rain can actually be a benefit because it creates a low cost method of naturally cleaning panels.

As an example, although the Sahara Desert of northern Africa has a very high solar rank, it has limited access to water and is very remote. Thus when considering a financial investment in this area, one must consider more than just the high solar resource.