Feeling the heat

A bad sunburn should be enough to teach a person respect for the closest star to our planet. Sitting on a black leather car seat on a sunny summer afternoon should do likewise, especially if you happen to be wearing shorts. Even better, try leaning against the hood of that same car on that same day. And who hasn’t felt the scalding hot water coming out of a backyard garden hose that’s been baking in the sun?

The sun delivers an incredible amount of heat every second that it’s in the sky. When directly overhead, it delivers 1000 watts to each square meter. That’s the same amount of energy your iron consumes when you press your clothes.

In spite of all that, solar hot water systems are a tough sell. Why is that?

Before we get into it, let’s recap what a solar hot water system is. First, the purpose. It may simply heat up your pool. It may supply domestic hot water to a home or business – for showers, washing dishes, and doing laundry. It may supply hot water for heating a building, for example by means of a radiant floor. It may even (and this, I’ll confess, is an application that causes me to geek out vigorously, although I won’t spend any time on it today) provide building cooling. Yes, using heat to make something cool. Wild.

Solar thermal water heating systems have a number of key elements. The first and most visible is the collector. This may be just a series of tiny capillaries made of black plastic, arranged in a long panel that looks like a mat. It may instead be a flat glass plate over manifold copper pipes, easily mistaken for a skylight. Or, it may be a set of evacuated tubes arranged side-by-side. The collector typically sits on a rooftop, although it may be on a rack built directly on the ground.

The second element is the working fluid, which circulates through the collector to carry away the heat to where it is used. This may be simply water, as is the case with solar pool heaters. However, water has a very narrow band between its freezing point and its boiling point. If a wider band is required, a different working fluid is needed. For example, in a region with cold winters and hot summers, a good choice is a 50-50 mix of water and propylene glycol. This mixture will only freeze at around -26°C (-25°F) and boil at 144°C (291°F).

Up next is the heat exchanger. In pool heaters, there typically isn’t one – the sun-heated water mixes directly with the rest of the pool water. For systems with a non-water working fluid (like the glycol mentioned above), in the heat exchanger the working fluid flows past one side of a flat metal plate, and the water flows past the other side. The glycol heats the plate, and the plate heats the water.

Finally, there is storage. Again, with pool heaters this element is absent. For other systems, the hot water tank is not much different from a typical water heater tank, except there is no electric element or gas burner at the bottom. The water circulates through the heat exchanger and back into the storage tank until it reaches the desired temperature.

In summary, the working fluid is heated up in the collector, it gives up its heat to the water in the heat exchanger, and the heated water is stored until it is needed.

All that is simple enough. So why are these systems so rare?

First, the sun suffers from Rodney Dangerfield Syndrome – it don’t get no respect. People just don’t seem to believe that a heater that uses sunshine could work, or work well enough to ensure, say, a suitably hot shower. This despite all the lessons we repeatedly learn about sunburns, hot car seats, hot car hoods, and hot water in garden hoses. The sun is plenty hot. It’s photosphere is 5500°C (9900°F), after all. Perhaps we take it for granted because it is such a familiar, everyday thing.

I had a personal and novel experience with the reality of sun-heated H2O this week. I was on the roof of a new retirement complex, doing the finishing touches on an eight-panel solar hot water system. We put some water through the array to flush out any debris and check for leaks. The leaks were easy enough to find, as there was steam – yes, steam – shooting out of them. The panels were hot enough from the mid-April Canadian sunshine to flash cold municipal water into steam. (We fixed the leaks and had the system up and running the next day.)

Second is the issue of timing. People think about when the sun is hottest – high noon – and compare that with when they most want hot water – for their shower first thing in the morning. What’s the good of hot water if it’s not hot when you need it? The answer is that the hot water stays hot for quite a bit longer than many would imagine. Anyone that’s used a double-walled, vacuum-insulated container like the ones made by Thermos will realize how well a properly-designed vessel can retain heat. One 100-gallon storage tank that my company installs is rated for a loss of 5°C (9°F) per 24 hours. To provide you with a hot (40°C, or 104°F) shower at 7AM, your system just needs to have heated the water to 42.5°C (109°F) when it calls it a day at 7PM the prior night.

That raises the third issue – reliability. The system may work just fine, but what if the sun doesn’t shine? A string of overcast days would make for a string of cold showers if your only source of hot water is sunshine. That is absolutely true, and that is why solar thermal hot water systems are rarely implemented without some form of backup, typically electrical.

The last issue, and the one that is the biggest barrier to wider adoption of solar thermal hot water systems, is economics. Four years ago, the price of natural gas was at an all-time high and people were looking very seriously at alternatives. Today, largely because hydraulic fracturing technology has offered up huge new reserves, the price of natural gas is one-seventh what it was. Solar thermal can only compete in areas without natural gas service, where electric water heaters are the only other option.

There’s only so much natural gas in the ground. Inevitably, the price will rise again. However, until that day comes, solar thermal hot water systems will be limited to applications where government subsidies are available, and locations where natural gas is not available.

But in those applications and locations, it is real, it works, and it is reliable.

And the fuel is and always will be free.


A chill wind from across the water

Neighbours? What neighbours?

A new US consortium. A year-old Canadian moratorium. On the Great Lakes, the wind is blowing in a completely different direction depending on which side of the border you find yourself. The US has the right idea. Canada does not.

What’s so special about offshore wind energy?

The first answer will be obvious to anyone that has worked offshore – principally oil and gas production facilities, or (as in my case) construction of the same. It’s a dangerous, alien, unforgiving environment. Blowing wind and crashing waves exert astounding forces on artificial structures. Ice, be it in the form of sheet ice, icebergs, or just build-up of ice on exposed surfaces, can make short work of insufficiently stouthearted designs. Salt water in particular is extremely harsh; there is an entire science dealing with protecting pipelines, pilings, and other (usually) steel construction elements from corrosion. So offshore wind energy facilities have to be much more robust – and are hence much more expensive – than their onshore brethren.

The second answer will be obvious to any sailor, especially the kind of sailor that worries about whether to hoist a sail or keep it furled. On open water, the wind blows with much more strength and with much more consistency than it does across land. Humans have taken full advantage of this fact for thousands of years, harnessing wind power to propel their vessels across lakes, seas, and oceans. If you’re in the business of converting wind power to electricity, offshore you’ll find a much higher capacity factor – meaning the amount of output that a given wind energy installation actually produces compared to what it is theoretically capable of producing.

The third answer will be obvious to anyone – there aren’t any people around. Onshore wind farms have evoked considerable controversy, as I discussed in my March 22nd post, Tilting at windmills. Most objections have come from people who don’t like the idea of having wind turbines located close to their homes. Needless to say, this is not an issue when the nearest homes are scarcely if at all visible across an expanse of open water. When you go far enough from land, even the birds become rare – if you can’t nest, if you can’t even land, you can’t live.

So although it costs more to get in the game, you can produce more power offshore, and you don’t have to worry about disturbing the neighbours. If the particular offshore location you’re considering is the Great Lakes, you have the added bonus that the environment is kinder and gentler than, say, the North Sea – fresh water rather than salt, meaning less corrosion; much more modest winds and waves; and a far less significant threat from ice. All without producing the greenhouse gases or radioactive waste that go with other key power generation technologies. What’s not to like?

Europeans have voted with their collective pocketbook. The European Wind Energy Association reported that at the end of 2011, there were a total of 1,371 offshore wind turbines in production spanning ten European countries, with a total generation capacity of 3,813 MW. That was up from 1,136 turbines in production one year prior. Those 235 new turbines represent an investment of €2.4 billion (US$3.1 billion).

The US has caught the offshore wind bug. On March 30th, President Barack Obama announced the signing of a Memorandum of Understanding between five US states and several US federal government agencies, intended to encourage the development of more offshore wind energy projects on the Great Lakes. Proponents of the initiative expect that it will create jobs and increase energy security.

Ontario has the most ambitious green energy initiative out of all the Canadian provinces, promoting expansion of wind, solar, and biomass energy generation capacity through a Feed-In Tariff (FIT) program. In spite of that, in February of 2011 the Ontario government placed a moratorium on offshore wind development in the province. Since Ontario is the only province with any of the Great Lakes within its territory, its moratorium effectively freezes any offshore wind energy on fresh water in the entire country.

What is up with that?

There are two reasons – the first being the reason which the Ontario government presented to the public, and the second being the real reason. The reason then-Energy Minister Brad Duguid offered is that not enough is known about the effects on human health of wind turbines in fresh water. That, of course, is silly – you would do as well to fret over the effect of emperor penguins on human health, because they are as likely to come in contact with people as offshore wind turbines.

The real reason is as both a sop and a goad to the anti-wind lobby, principally Wind Concerns Ontario. The sop: Folks, we hear your concerns, so we’ll stop one aspect of wind energy development. The goad: There’s no reliable science behind any of the WCO concerns, but we acknowledge that there is a gap in our scientific understanding of offshore wind turbines standing in fresh water, so we’ll sit tight until that science is clear.

Apparently the Ontario government has no sense of urgency to get the question answered so that the moratorium might be lifted (or, indeed, made permanent). There was no follow-on announcement of a research program to assess the health impacts of wind turbines located offshore in fresh water bodies. No rush, right?

But now the pressure is on. The Americans have taken up the challenge of offshore wind energy development on the Great Lakes. They apparently do not share the Ontario government’s concerns about health impacts. They have a broad-based coalition with both state and federal support. Ontario will never have anything remotely similar as long as the current fossil-fuel-fixated federal Conservative government remains in power.

Ontario needs to reverse its stance on offshore wind, commissioning health studies if necessary, and then getting on with the job. Canada has within its grasp the opportunity to be the first to innovate with a promising new technology, to build a new industry, to create jobs, and to establish itself as a world leader. If nothing changes, Canada will be handing this opportunity to the United States on a silver platter, and it will be the Avro Arrow debacle all over again.

The real China Syndrome

Welcome <cough> to <cough> Beijing

Dark clouds are gathering in the east.

We depend on China for all manner of manufactured goods. Consumer electronics, cookware, children’s toys, and virtually any other item you can name – or purchase – all come with the familiar “Made in China” label. In 2009 the country overtook Japan to claim the #2 spot on the World Bank rankings for Gross Domestic Product (GDP), second only to the United States. And with an annual growth rate that has hovered around 10% for the last four years, it won’t be long before China tops the charts.

The energy it takes to keep all that industry running is astounding. In 2009 China used 2,257 Mtoe (million tonnes of oil equivalent), making it the world’s top energy consumer. The International Energy Agency estimates that in 25 years, China will consume 70% more energy than the United States.

Where will all that energy come from?

The answer is enough to any environmentalist blanch. The country’s 12th Five-Year Plan, encouragingly, calls for lower carbon intensity and more diversification of energy sources. Despite this, two of the most significant sources of energy that will drive Chinese growth are nuclear and coal.

A burgeoning Chinese nuclear energy sector should be unsettling news both within the country and without. The Chinese people will have to bear the high cost of nuclear power and the near-eternal commitment to safeguard radioactive waste. Likewise, they will have to accept the risk of nuclear disasters. There are more stakeholders beyond the country’s borders; nearby countries like Korea, India, and Japan will also have to live with the danger of a Fukushima-style catastrophe.

The effects of coal will reach even further. A 2007 MIT report stated that China was building new coal-fired generation facilities at a rate equal to two 500MW plants per week. Olympians surveyed with dismay the dirty Beijing skyline, as much a result of the country’s addiction to coal as it is the massively polluting two-cycle engines of countess mopeds and motorcycles. While particulates and acid precipitation from burning coal take their toll on the Chinese, the carbon dioxide will be felt across the globe as temperatures rise and weather patterns increase in chaotic intensity.

Were China a democracy, there is at least a chance that the people might demand change. North American democracies are hardly a model for decisive action against climate change, but Europe has taken a firm stand. Germany has become a leader in renewable energy technologies and has made huge strides towards reducing its dependence on fossil fuels. Denmark has done likewise. All this because the voters have demanded it. There is no such pressure on Beijing – politburo members are accountable neither to the international community nor to the Chinese citizenry.

The term “China Syndrome” is used to describe an extreme-case nuclear disaster. In this scenario, the core of a nuclear reactor melts down, burning through the containment vessel and the secondary containment building, and continues right through the earth’s crust. In a stroke of childish hyperbole, the radioactive mass eventually emerges on the other side of the planet – China.

A more modern version of the China Syndrome would be this. The authoritarian regime ruling the world’s most populous country is bent on acquiring wealth for its elite members (and perhaps, through economic trickle-down, the rest of the citizenry). It pursues this agenda in spite of international pressure to clean up its environmental act. It rationalizes that the developed nations had their turn at the messy carbon trough, so why can’t the up-and-coming economies? Resources are consumed and greenhouse gases are emitted at an eye-watering rate. Global CO2 levels rise relentlessly. The world rides an express elevator to complete ecological meltdown.

The original China Syndrome has never happened (Fukushima may be the exception). However, the modern China Syndrome is taking place at this very moment.

Can anything stop it?

The avenue of formal, binding, global, multilateral agreement has failed. The Kyoto Protocol offered some hope, but that evaporated last year at the Durban Climate Change Conference. The so-called Durban Platform amounts to nothing more than hitting the snooze bar until 2015. Few are optimistic that anything meaningful will be accomplished then either.

As I pointed out at the beginning of this post, China did not get to where it is by catering to the needs of its own population. Its growth has been, and continues to be, fuelled by exports. China consumes coal, but we consume the products that the coal creates. If we want to know the real culprit, we have only to look in the mirror.

Consumers in developed countries have demanded more and more for less and less. To retain market share, manufacturer after manufacturer has been forced to relocate operations to locations with the lowest cost. All that we have demanded is that the products we buy be cheap – we don’t give a tinker’s cuss about the environmental impact. Heck, we don’t even care much about the quality. Who cares if it breaks, if it’s so cheap that you can just buy another one?

The only way the China Syndrome can be stopped is if we change our mindset, and our purchasing patterns. Manufacturers provide us with crappy merchandise produced in an utterly unsustainable way for one simple reason – we haven’t demanded anything different. If we demand products that are manufactured in an environmentally responsible way, producers have no choice but to supply them.

The most innovative players will identify environmental responsibility as a differentiator. Such products will, at first, be able to command a premium. With time, competitors will get in on the act. Hopefully, before too long, sustainability will be table stakes – producers simply won’t be able to sell goods that were created in a way that depleted the earth.

The clock is ticking. China’s trade balance took a sharp dip into deficit recently, meaning that the value of imports exceeded that of exports. The domestic Chinese market is growing as more and more citizens reap the benefits of economic advancement, and the middle class becomes larger and larger. Soon, Chinese firms will be able to profit without exporting. And any leverage the outside world has over Chinese environmental direction will vanish.

We’ve got the power to avert the modern China Syndrome. But we won’t have it for long.