Living Off the Grid: Solar Power for Homes, 1994 Guide

Incremental improvements have made solar power for homes a more viable alternative than it was in the 1970s, when cost and performance issues eventually blunted enthusiasm for the technology.

solar power for homes - output wave forms
The smooth line of the sine wave means that power is delivered smoothly to peak capacity. Square waves deliver power quickly and in one big burst. Modified square waves are intermediate between sine waves and square waves.