Advocates say this, or something like it, may be an answer to the world's food problems.
Doubtful. The starving hordes are starving because
A) they've bred until their country can't support its population
B) they're at the technological level where poking holes with a stick and fertilizing with human waste are considered valid methods of farming.
Before you can hang a grow lamp, you need a whole industrial infrastructure from the light to the power station to its fuel supply. And that takes money, and an effective government, with diplomatic and military ancillaries, to acquire and maintain that fuel supply.
Yeah, you can grow stuff indoors under electric light - orchid and rose growers have been going it since the late 1800s... but not in the kind of countries that can't feed themselves to start with.
edit: the government part is no joke. The Soviet Union was a nuclear power and landed probes on the Moon and Venus... and they lost tens of thousands to famine during that time. Gross mismanagement of resources forced them to buy food from the ideological enemies.