No - because 2.7% (or 0.7 efficiency difference) increase is not insignificant when you scale up. As an analogy, think of what 0.7% tax saving would mean to you

No - because 2.7% (or 0.7 efficiency difference) increase is not insignificant when you scale up. As an analogy, think of what 0.7% tax saving would mean to you annually. In reality solar-cells and batteries are not at all cheap to install and maintain. We can scale up the solar cells and collect more energy. However, that needs more surface area to be covered with these panels. We still need better ways to store the energy efficiently.