According to a Renewable Power Purchase Arrangement (PPA), a Renewable Energy Service Company (RESCO) will install and maintain a customer's solar power plant at their site. The RP, which refers to a typical 10-year contract, results in monthly payments for a percentage of the customer's power generated. The Opex model reduces investment risk and avoids the expense of creating a Capex investment, enabling customers to pay for only the actual power produced with zero large assets. This creates a more cost-effective Opex model upfront. Even with a Power Purchase Agreement, the energy is significantly cheaper than grid power. The OPEX model is well-suited to small businesses with planned growth aiming to incorporate more environmentally friendly processes.