Use 3 - power the National Grid

Purely in the interest of science, if you can make electricity from a lemon, how many lemons does it take to power the national grid?

To answer that question we need to know 2 things:

1. How much electricity does 1 lemon produce.
2. How much electricity does it take to power the national grid the conventional way.

Well, from the experiment we carried out, our lemon produced 1.5 volts of electricity, and to get the answer to the next question we emailed the national grid (transco) and asked them. We also asked them if they could answer the original question to save us from working it out for ourselves, and see if they would take us seriously!!