Anyone looking to procure renewable energy for a business in Japan has four basic options: purchasing renewable energy certificates, signing up for one of the renewable energy plans offered by power retailers, building your own generation capacity, or signing a corporate PPA with a power generator.

Naturally, each option comes with advantages and disadvantages.

Option #1: Purchase of Renewable Energy Certificates

Renewable energy certificates are used by corporate power consumers to offset carbon emissions and to prove they consume “green energy,” at least on paper. The main advantage is the ease of purchase and the flexibility of procured volume.

The downside is that the actual power that the certificate buyer consumes doesn’t necessarily come from a renewable power source. By extension, purchasing certificates doesn’t directly result in new renewable capacity added to the grid.