Buy outdoor solar camping lamps. Leave them outside all day and bring them in at night. You may need some more illumination faster you do buy conventional lamps, you have to use compact fluorescent bulbs.
To get to Pulau Ubin from the mainland, you should catch a train to Pasir Ris and then catch a bus for the jetty at Changi Village. From there you need to catch a bumboat to the city. The bumboats sit 12 people and the owners will expect that many people until they leave. The boat fare is $2.50. On a weekend the boats will fill up in too busy. You might have to wait a little longer on a weekday, of course. The crossing itself takes about continuous.
One for the first an individual may should work out is what you'll be utilizing the generator to. This is important because you don't want to buy a short 50Kw Diesel Generator that is needed for a job, or vice versa. So formulate exactly this will supply for before you consider buying certain.
How will you transport your generator?