The most frustrating thing for a group of enthusiastic engineers is to have their efforts and aspirations thwarted by bureaucracy. But that’s exactly what happened when our shipping company refused to give us our container or even accept any form of payment. We spent an unproductive and relaxing two weeks in Darwin without a car to work on. However, what we achieved in the following fortnight after we finally got our hands on the car cannot be overstated. The car arrived in a “working” condition (we’d done some driving back in the UK at Bourn Airfield) but getting the vehicle race-ready took a huge amount of proverbial elbow grease and midnight oil.

We successfully fitted new lights and LED drivers, tested new driver controls and telemetry, performed solar battery charging tests and re-wired a few things that we’d never got around to in the UK, including the rear-view camera. The mechanical guys chipped in with a new set of wheels, worked out how to fit the Michelin tyres (and then taught a couple of other teams how to do the same) and fitted a brand new canopy. We painted the car and stickered her up with new sponsor logos, after BA successfully lost our first logos package somewhere between the UK and Sydney.

We always knew that testing was going to be critical to race success and not having the car for two weeks effectively robbed us of two weeks’ testing time. Despite this, we spent a couple of days out on the Cox Peninsula road just driving and practising convoy communications. I like to think of testing as deliberately causing problems so that they won’t happen when it actually matters. Pretty much anything that can go wrong in a solar car at some point will, and of all the things that can go wrong, the majority are electrical. The main problem that we “caused” during this testing period was battery related. One of our 5 Cell Management Modules (CMMs) decided to fail in a short-circuit state. These boards had until this point been doing a stellar job of keeping all 80 cells nicely balanced, but this fault destroyed two cells (and their two replacements) and meant we had to replace the CMM. Fortunately we’d brought two spare CMMs with us, unfortunately one of them didn’t work, and the other had an ID that conflicted with one that was still working. Some epic software bodging by “Batt-man” Ed meant we found a working solution. The CMM boards later threw regular over temperature faults and started physically shedding capacitors at an alarming rate. We fixed these problems as they appeared, but were nevertheless quite frustrated by such issues on supposedly reliable hardware. When you build a car, you half expect your home-made components to go wrong, not the stuff built by professionals.

We began the race quietly optimistic that we’d (perhaps) finish the 3000km on solar power. The first day we started fairly low on the grid after putting in a (sensibly) cautious qualifying lap at Hidden Valley due to concerns about the suspension and the new wheels. But when you’re not competing for the top 5 positions, grid position is relatively unimportant in a 3000km endurance race. We got off to a flying start and overtook the usual first hour breakdowns on the way out of Darwin. We had an exciting but (thankfully) uneventful few hours driving. The inevitable first problem occurred when the driver controls stopped functioning. It took the best part of an hour to work out where the problem was and find a solution. We fell back on an earlier version of the controls and carried on driving. Later inspection of the circuit would reveal that an inductor in the power supply had come loose causing total power loss to the steering wheel. The result of this fault was that we were behind our ideal race pace and would struggle to make Katherine (the first control stop) in time. What we failed to realise was that this was not critical and that we could have missed this control stop and perhaps adjusted our strategy accordingly for the following day. Instead we made the mistake of thrashing our car a bit too hard, driving at 20kph faster than we realistically could sustain. We ended up with what we assumed was a flat battery and were forced to trailer.

Another problem also contributed to our first day disappointment. Our telemetry system failed due to a blown fuse in the chase car’s 12V system. Another case of off-the-shelf components failing and lack of testing left us without good battery data while we drained a bit too much juice. As it turned out, the battery wasn’t completely drained, but one or two overly-discharged cells had triggered Low Voltage Protection (LVP). This fault was quite possibly a result of having to replace cells before the race because of the aforementioned CMM short-circuit issue. When a battery pack isn’t given enough opportunity to balance itself (which it wasn’t in this case) the entire pack capacity can be limited by only a few unbalanced cells. If the CMM issue had been triggered earlier with more testing, we would probably have started the race with a well-balanced pack and had access to a bit more capacity on day 1.

By now you might have noticed a common theme in my musings – we didn’t test enough. If shipping hadn’t been so problematic, we might have used our relaxing two weeks in Darwin more productively by (money permitting) spending several days driving the Cox Peninsula road in convoy.

By day two we’d established what went wrong on day 1, and put in place the necessary fixes. This required some proper Outback Engineering and the WSC observer looked on with a concerned expression as we fired up our generator and plugged various cables into the car. After we’d explained (across a slightly difficult language barrier) that we weren’t charging our battery but just powering a couple of laptops and a soldering iron he left us to it.

The rest of the race passed without major technical incident. From this point onwards we encountered all the problems afflicting every team: haze from a large bushfire on days 1-3, bushfires closing the road on day 3, strong crosswinds, lighting storms, quite a bit of rain, and the general lack of sunlight. Every encounter with other teams at control stops began with some engineers standing in a circle looking dejectedly at the clouds and pointing hopefully at a small patch of blue sky in the distance. Towards the end of the race we found ourselves doing a kind of “inverse storm chaser” manoeuvre where we’d trailer as fast as we could away from the bad weather and then spend a few hours at a rest stop where the sky would be lighter or (if we were lucky) we’d get 30 minutes of direct sunlight.

Squeezing every last ounce of energy from a solar electric vehicle is strangely satisfying, especially at the point in a solar race when everyone is resigned to not finishing on solar power alone and what really matters is the number of solar km covered.

So we finished the race in 25th position after covering 1487km on solar power alone. It’d be a lie to say that we’re completely happy with our position. Whilst better weather would almost certainly have enabled us to cover over 2000km, it would also have similarly improved the performance of the other 28 cars who also failed to complete the full distance. We were slightly unlucky to be caught at the back of the pack after day 1 as cloud cover advanced from the north and hit the slowest teams hardest, and we certainly had our share of bad luck with technical issues. But the fact remains that we lost over an hour to an electrical problem that would have been solved before the race if we’d tested more. The resulting sprint to Katherine cost us (and our battery) dearly, and if we’d driven more conservatively we wouldn’t have been forced to trailer on day 1.

One reason for our excessive energy use on day 1 is that our car simply weighed too much. The first half of the race was much hillier than any of us had been expecting and this took a heavy toll. Even with perfect weather, no technical problems, and perfect race strategy, it’s difficult to say whether our current vehicle is genuinely capable of finishing the race on solar power.
We began the year with plans to build a new car, but also with several thousand pounds of debt. Initial optimism, excitement and inspiration gave way to frustration as the decision was made to re-use our 2009 vehicle due to financial issues. This was clearly the right decision at the time – we might never have made it to Australia at all otherwise. To build a competitive solar car requires strong financial backing, and at the start of the year we simply didn’t have this. The other limiting factor is the time required. CUER is composed entirely of Cambridge undergraduate engineers. The Cambridge MEng is demanding and time consuming and where the best solar car teams in the world have a team of full-time engineers on an 18 month sabbatical from their studies, million dollar budgets and dedicated production facilities, we’re the equivalent of a few guys with spanners in a shed. With these constraints and the best will in the world (such as the 2009 team’s: they actually built a new car) you’re never going to build a world-beating vehicle.

Our solar car remains the best in the UK, an achievement we’re immensely proud of. But we recognise that we’re currently not going to beat the top Japanese and Dutch teams at their own game. The World Solar Challenge has made a handful of engineers across the world extremely good at building and racing solar-powered cars that have very little real-world use (but are damn good fun). It’s my personal opinion that CUER should adopt a very “Cambridge” attitude and build a genuinely innovative and perhaps slightly more practical vehicle. This isn’t an easy task and several conditions would make this easier, summarised below in my own personal wish-list:
• A bigger budget (we currently operate with roughly negative money…). This would probably require a large, dedicated business team and might include financial support from the university/department itself.
• A strong dedication of time from perhaps a 10-strong team of undergraduate engineers. Ideally a sabbatical year off the master’s course to concentrate on building the car.
• Dedicated lab space and facilities. Many teams have their own space to build their car. We beg, borrow and steal space from various labs and do a lot of our work in a car park at the back of the department. Other student-run projects in the department suffer from the same lack of facilities. It’s a pretty sad state of affairs when the best university in the world can’t support its own students in such fantastic projects.

Having one or two of the items from the above list would greatly improve our chances of doing something quite special next time around, especially considering at least half the 2011 team are remaining in Cambridge with either PhDs or employment. We’ve all got some fantastic ideas and the technical experience and know-how to put designs into practice.

Having completed the World Solar Challenge is no mean feat, and CUER can be extremely proud that it has now entered twice and still has a fully-functioning solar car. The battery is still workable, we have a robust wiring system, our old and battered solar array still gives us a good power output, and Douglas’s telemetry system performs admirably. Despite the issues, WSC was the experience of a lifetime for all of us.

This is not another article about Why This Is The End For Nuclear or How Fukushima Made Me Stop Worrying And Love The Bomb. They are already clogging the internet and attracting all sorts of insane online versions of the sandwich board screaming “REPENT. THE END IS NIGH”. Instead, it is an attempt (of which there have also been many) to inject some perspective, some rationality and some information into the energy debate, which has been running for far longer than the past two weeks.

Although CUER is a group firmly focused on renewables, between us we do hold an interest in many other forms of power generation – of which just one is nuclear. CUED runs a particularly popular course on Nuclear Engineering and for many of us it is an eye-opener. The study of a subject at university level is probably as unbiased an exposure as it is possible to get these days and is, one would hope, sheltered from excessive outside influence by Big Oil or Nuclear Shills or Chuck Norris. It’s difficult to lie about something when you must derive it from first principles, and if you try, there is always someone smart enough to spot it. You know – the annoying kid that sits right in the front row and always corrects the lecturer, and who never leaves the university until s/he becomes the lecturer, and suffers the indignity of being called out on every missed minus sign by the next generation of academics. The kind of person who cannot so easily be bought, because if they cared about money, they would have chosen a career path other than academia. The engineers who can be bought (and it’s a good 20% of the intake) usually end up working for Goldman Sachs. It’s a very neat system of quality control.

However – after receiving such an education from people who are usually world experts in the field, it becomes rather frustrating to see misinformation and rumour spread to such a degree as has lately been the case. It gets to the stage where a sort of triage is necessary to weed out the is-this-the-next-Chernobyl crowd, the Sellafield-gave-my-dog-cancer crowd (closely related to the power-lines-gave-me-hemorrhoids crowd) and the why-don’t-we-just-use-cold-fusion-it-really-works* crowd. There are many valid arguments against the proliferation of nuclear power. These are not they.

Everything carries risk. Fossil fuel power carries risk. Coal-fired power stations transmit more radiation to their surrounding environment than do nuclear power stations of the same energy output. Renewables carry risk. While the world’s media was distracted with the panic over impending doom bubbling away at Fukushima Daiichi, it seemed to miss the collapse of a hydroelectric dam which, according to reports, swept away more than 1800 homes and killed many.  As engineers, we can never eliminate that risk, but we can manage it, and we can design for it. This is the approach taken with nuclear power. Discussion of Chernobyl is often irrelevant to modern reactors. Not only was the reactor poorly designed, but the safety systems and procedures in place were not properly followed. Moreover, before 1986, there was no fear of nuclear power – there was no ‘Chernobyl incident’ to act as a focus for public opposition. These days – even the mention of the word ‘nuclear’ is enough to set off an unfounded panic. Anyone trying to convince a government to allow them to build a reactor had better be very sure of themselves. Safety systems within safety systems – all of them passive – that is, that require no activation but will, by default, engage automatically unless they are prevented from doing so – are the norm in the newest reactor designs.

Sadly, these new designs are currently just that – designs – because so far few governments have had the courage to stand up to vehement public opposition to nuclear power. Three Mile Island was one of many nails in the coffin of the US nuclear industry. Although the release of radioactive material following the meltdown was minimal and had little effect on the surrounding environment, the close-to-home incident was enough to set off several enormous anti-nuclear protests. No doubt this was exacerbated by the release of the movie The China Syndrome only days before the incident. The result of this kind of unfounded opposition has been to block the construction of newer, safer reactors and instead prolong the life of older reactors that should be decomissioned, because we need the power.

Many of those holding anti-nuclear views do not necessarily have an engineer’s understanding of other sources of power generation. CUER itself has long documented the struggles with efficiency and the high costs imposed by solar technology. Wind power, tidal power, hydroelectric – all these energy sources are valuable, and should be exploited, but they are not risk-free and neither are they a power generation golden egg. One of the biggest problems with abandoning fossil fuel power generation is that of load following. A power plant does not just sit there unresponsive – it will typically generate a constant baseload and respond to dips and surges in energy demand – the classic “30 million people putting the kettle on at half time” scenario. Currently, fossil fuel power stations are the only power source we have capable of doing this. True, there are potential solutions involving pumped-storage or an international energy grid. These are viable alternatives that should be explored and developed – but that will take time. Nuclear energy is one option – of many – that may help us bridge the gap between our the unsustainable present and the necessarily sustainable future.

Engineers work with scientific evidence, with mathematical modelling, with probabilities and safety factors and we had better make damn sure we get it right, because lives depend upon it. A modern nuclear reactor is not something that has been cobbled together by Acme for an anthropomorphised roadrunner-obsessed canine. There are problems with the nuclear industry – waste disposal, proper regulation, control of radioactive material – these should be faced, addressed and solved. That is what engineers do. The World Trade Centre remained standing for a reasonable amount of time even after it got hit by over 60,000 kg of burning aircraft, because a bunch of engineers thought about the worst possible loading it could suffer, and then overdesigned. Fukushima Daiichi survived an earthquake 10 times stronger than it was designed to withstand. Nuclear power may have started out as a US-Soviet undercover plutonium production racket, but it is well-controlled and well-integrated into our energy mix today.

It is therefore highly frustrating to watch so much science and considered design get thrown out of the window because somewhere along the way a news story about an overheating but still contained reactor snowballs into FUKUSHIMA TO BECOME A NUCLEAR WASTELAND UNLESS CHINA PANIC-BUYS SALT. It is frustrating when offshore wind farms are dismissed because someone on Question Time heard some guy say that they beach whales and kill fairies. It is frustrating when renewable transport alternatives are ignored because global warming is just a conspiracy between all the climate scientists in the world and communist zombies. All these things are branches of the same, scientifically illiterate tree. It seems that so much science policy today is made as a result of bad advice or public pressure – and that is wrong. We need to come up with energy solutions – not just for power generation but for transport – and decisions on what routes to pursue, especially at a time of such restricted funding, should be made rationally.

By all means, dismiss nuclear power as a viable option for the future – but please provide evidence and alternatives. Otherwise, you’re just one more irresponsible internet drone who causes real fear and real detriment by joining in with the chorus of uninformed voices telling anyone who will listen that standing next to a microwave when you’re pregnant will make your baby gay. And that somehow that’s a bad thing.

***

*It doesn’t. It really doesn’t.

See here for an interesting look at relative radiation doses.

A lot of noise has been made recently about Carbon Capture and Storage technology, most recently with the UK Government backing the building of four new coal fired power stations subject to them implementing Carbon Capture and Storage (http://news.bbc.co.uk/1/hi/uk_politics/8014295.stm).

CCS is a very attractive idea, which basically does exactly what it says on the tin, captures the carbon dioxide generated when the coal is burnt and then stores it rather than releasing it in to the environment.  This is attractive because there are still large reserves of coal available, and the main reason for not using them is not because of the cost of extraction but rather their CO2 emissions.  Coal fired power stations have always been attractive as base power generation since they are able to change load comparatively fast (to match the generating power required) and are fairly easy to operate, well understood (the fuel is burnt, bosh!) and reasonably safe (for instance there is not the safety stigma associated with nuclear power).

There are three methods of Carbon Capture, pre-combustion, post combustion and oxy-fuel combustion.  Pre-combustion capture involves removing the carbon before the burning takes place, typically by gasification and the water-gas shift reaction, which produces hydrogen and carbon dioxide, the carbon dioxide is then captured and the hydrogen is used in the power station.  Post-combustion capture scrubs the exhaust gases of CO2 and Oxy-fuel combustion burns the fuel in pure oxygen, allowing the CO2 to be extracted much easier (there is predominantly only CO2 and H20 in the exhaust).

The storage element will be done by pumping the gas into either empty oil wells (as is already done in some rigs in the form of Enhanced Oil Recovery (EOR) to extract more oil from near empty wells), or into deep sea saline aquifers.  This presents two main difficulties, firstly the need to transport the CO2 to these locations, and secondly who is responsible for monitoring them (and who gets to use them!) since they will be offshore, and this means there will be the need for international co-operation.

It should also be noted that the use of CCS technology will inherently use more power than a similar facility without the technology, and so is not likely to be economically viable until the market is levelled, either by making the use of the technology mandatory, or offering some incentive (such as tax on CO2).  The UK Government has already set up Carbon Budgets (see the Climate Change Act 2007).

There is loads of information available on the internet about this technology, and it has featured recently in many issuse of the IMechE magazine Professional Engineering (www.profeng.com).  CCS provides a potentially eco-safe, and politically secure energy supply for the UK, as well as ensuring steady supply and looks like a promising area to be in at the moment…

- Mike