The writer who challenged the perceived environmental advantages of electric cars (“Going Green?,” July 14-20) makes an excellent point. Where will the electricity to recharge the batteries come from...generating stations that burn natural gas, oil, or coal? Or nuclear power? Or wind farms? None of these electricity sources is very green. One possible answer might be solar energy. Imagine shopping mall and factory parking lots roofed over with thousands of acres of solar collectors. Visualize a system where a car could be plugged in and recharged while its driver was shopping or at work. Rather than generate electricity at a few distant power plants and distribute it by inefficient and environmentally damaging transmission lines, a decentralized solar system would generate electricity locally and feed it into the existing grid. Such a system would take full advantage of the inherent efficiency of electric cars and be truly “green.” Corporate giants like Wal-Mart could lead the way on this.