Other Renewable
Energy Technologies

Biofuel

FAQ

Q1.	Can I use rice to produce biofuel?
Ans:	Since the starch content of rice is high, it can be used to produce ethanol by fermentation, just as the process used in beverage alcohol production. However, the low oil content in rice renders it not suitable for the production of biodiesel.

Q2.	How can plant biotechnology benefit the development of biofuels?
Ans:	The feedstocks of biofuel are mainly cash crops, such as sugar cane and corn for the production of ethanol. That is one of the reasons that the cost of biofuel is higher than that of fossil fuel. Researchers are working to develop genetically engineered enzymes, yeasts and bacteria to produce biomass ethanol from just about any plant, tree or agricultural waste. This would dramatically reduce the cost to produce ethanol.

Q3.	What is octane number?
Ans:	Octane number, in a scale of 0 to 100 for conventional fuels, is a value used to indicate the resistance of an automotive fuel to "knocking". It is measured relative to a mixture of iso-octane and heptane. Higher octane number indicates a higher resistance to knocking. It is possible to have fuels with octane number greater than 100 (such as ethanol and LPG) as iso-octane is not the most knock-resistant substance available.

Q4.	Can I fuel my car with biofuel?
Ans:	Normally, petrol blended with less than 10% bioethanol can be used directly in petrol engine cars without engine modification. Biodiesel at any percentage can also be used in diesel engine cars. However, car owners should ensure that fluorocarbon rubber is used in the fuel system instead of nitrile rubber which will be dissolved by biodiesel. Besides, biodiesel dissolves and release diesel deposits in the fuel system and this will clog filters. Therefore, car owners should seek technical advice from car manufacturers before switching to the use of biofuel.

Q5.	Is biofuel commercially available in Hong Kong?
Ans:	No. Bioethanol and biodiesel are not available in filling stations in Hong Kong.