Macau Matters | Solar Powered Railways

Richard Whitfield

From my previous musings it should be clear that I am a big fan of renewable energy – we must get away from burning fossil fuels if the human race is to survive on planet Earth. Make no mistake, the planet will survive until the sun blows up, but the conditions needed to support human life here can easily be eliminated if the ecosystem changes to a new equilibrium state because we have pumped too much CO2 into the atmosphere.
Solar power is one of my favorite renewable energy sources. It is largely solid state, i.e. no moving parts to wear out and be maintained, the power source will not run out till the sun stops shining and there are few economies of scale so that energy generation plants can be incrementally added as needed to minimize initial capital investment and widely distributed near to points of demand to minimize transmission losses.
There are some stupidities I regularly see with solar power that I cannot understand. Firstly, there is no point in building solar power “panel farms” far from cities because it just maximizes transmission losses – it is much better to put the panels in cities from an efficiency perspective. Secondly, there is no point in using photovoltaic panels to generate electricity and then use the electricity to heat water; photovoltaic panels only have 20+% energy collection efficiency, whereas solar thermal panels can have 80+% efficiency to directly make hot water.
There is a very good experiment underway in the UK where they are putting photovoltaic panels beside railway tracks and using the electricity generated to power the trains. The experiment is being done because in Europe the capital costs of new renewable energy generation plants are becoming lower than the costs of comparable new fossil fuel plants. Additionally, the tracks are just meters away from the panels so there are virtually no transmission losses. Moreover, trains normally use DC power so that are no DC-AC power conversion losses. Finally, there is plenty of space along the railway tracks to add more panels as the approach proves itself economically. And the panels can provide shade and rain protection over walkways, etc as further side benefits.
There is also a heritage railway in Byron Bay in Australia that is fully powered by photovoltaic panels on the train carriages and the train overnight storage/maintenance sheds. The proposed Hyperloop system for super-high speed trains also incorporates photovoltaic panels over the travel tubes to power the system.
This is the way that solar energy should be done. I see that Macau’s light rail has started operating, but I do not see a single photovoltaic panel anywhere for it – why not? Surely, the roofs of all the stations and covered walkways could be fitted with photovoltaic panels along with the sections of the track that are covered. And, the train carriages themselves could have rooftop panels.
Photovoltaic panels may not provide enough electricity to power the whole light railway – trains and stations – but it should provide a significant part of the total consumption. As important, it would be a great way for Macau to demonstrate its commitment to improving the environment. It would also support regional photovoltaic panel manufacturing and installation industries and help develop expertise in this important field in Macau to help diversify the local economy and establish a new “exportable” service industry. I am sure that many local and regional companies would like to be involved to showcase their expertise to all our tourists.
Why is it that we continue to see these kinds of “future living” experiments being done in other parts of the world, but not in Macau? We should be doing much more here but our government, universities and local industries are letting us down.