Category Archives: clean energy

Sleepwalking off a Cliff: Can we Avoid Global Collapse?

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‘Without significant pressure from the public demanding action, we fear there is little chance of changing course fast enough to forestall disaster’
Drs. Paul and Anne Ehrlich

WHO: Paul R. Ehrlich, Anne H. Ehrlich, Department of Biology, Stanford University, California, USA

WHAT: An ‘invited perspective’ from the Royal Society of London for Improving Natural Knowledge (the Royal Society) on the future of humanity following the election of Dr. Paul Ehrlich to the fellowship of the Royal Society.

WHEN: 26 January 2013

WHERE: Proceedings of the Royal Society, Biological Sciences (Proc. R. Soc. B) 280, January 2013

TITLE: Can a collapse of global civilization be avoided?

Dr. Paul Ehrlich has been warning humanity about the dangers of exceeding the planet’s carrying capacity for decades. He first wrote about the dangers of over-population in his 1968 book The Population Bomb, and now following his appointment to the fellowship of the Royal Society, he and his wife have written what I can only describe as a broad and sweeping essay on the challenges that currently face humanity (which you should all click the link and read as well).

When you think about it, we’re living in a very unique period of time. We are at the beginning of the next mass extinction on this planet, which is something that only happens every couple of hundred million years. And since humans are the driving force of this extinction, we are also in control of how far we let it go. So the question is, will we save ourselves, or will we sleepwalk off the cliff?

Drs. Ehrlich describe the multiple pressures currently facing the planet and its inhabitants as a perfect storm of challenges. Not only is there the overarching threat multiplier of climate change, which will make all of our existing problems harder to deal with, we have concurrent challenges facing us through the loss of ecosystem services and biodiversity from mass extinction, land degradation, the global spread of toxic chemicals, ocean acidification, infectious diseases and antibiotic resistance, resource depletion (especially ground water) and subsequent resource conflicts.

you have humans Wow. That’s quite the laundry list of problems we’ve got. Of course, all these issues interact not only with the biosphere; they interact with human socio-economic systems, including overpopulation, overconsumption and current unequal global economic system.

If you haven’t heard the term ‘carrying capacity’ before, it’s the limit any system has before things start going wrong – for instance if you put 10 people in a 4 person hot tub, it will start to overflow, because you’ve exceeded its carrying capacity.

The bad news is we’ve exceeded the planet’s carrying capacity. For the planet to sustainably house the current 7 billion people it has, we would need an extra half an empty planet to provide for everyone. If we wanted all 7 billion of us to over-consume at the living standards of the USA, we would need between 4 – 5 extra empty planets to provide for everyone. Better get searching NASA!

The Andromeda Galaxy (photo: ESA/NASA/JPL-Caltech/NHSC)

The Andromeda Galaxy (photo: ESA/NASA/JPL-Caltech/NHSC)

The next problem is that a global collapse could be triggered by any one of the above issues, with cascading effects, although Drs. Ehrlich think the biggest key will be feeding everyone (which I’ve written about before), because the social unrest triggered by mass famine would make dealing with all the other problems almost impossible.

So what do we need to do? We need to restructure our energy sources and remove fossil fuel use from agriculture, although Drs. Ehrlich do point out that peaking fossil fuel use by 2020 and halving it by 2050 will be difficult. There’s also the issue that it’s really ethically difficult to knowingly continue to run a lethal yet profitable business, hence the highly funded climate denial campaigns to try and keep the party running for Big Oil a little longer, which will get in the way of change.

The global spread of toxic compounds can only be managed and minimised as best we can, similarly, we don’t have many answers for the spread of infectious and tropical diseases along with increasing antibiotic resistance that will happen with climate change.

Helpfully, Drs. Ehrlich point out that the fastest way to cause a global collapse would be to have any kind of nuclear conflict, even one they refer to as a ‘regional conflict’ like India and Pakistan. But even without nuclear warfare (which I hope is unlikely!) 6 metres of sea level rise would displace around 400 million people.

One of the most important things that we can be doing right now to help humanity survive for a bit longer on this planet is population control. We need less people on this planet (and not just because I dislike screaming children in cafes and on airplanes), and Drs. Ehrlich think that instead of asking ‘how can we feed 9.6 billion people in 2050’ scientists should be asking ‘how can we humanely make sure it’s only 8.6 billion people in 2050’?

How can we do that? Firstly, we need to push back against what they refer to as the ‘endarkenment’, which is the rise of religious fundamentalism that rejects enlightenment ideas like freedom of thought, democracy, separation of church and state, and basing beliefs on empirical evidence, which leads to climate change denialism, failure to act on biodiversity loss and opposition to the use of contraceptives.

And why do we need to push back against people who refuse to base their beliefs on empirical evidence? Because the fastest and easiest way to control population growth is female emancipation. Drs. Ehrlich point out that giving women everywhere full rights, education and opportunities as well as giving everyone on the planet access to safe contraception and abortion is the best way to control population growth (you know, letting people choose whether they’d like children).

More importantly, Drs. Ehrlich want the world to develop a new way of thinking systematically about things, which they’ve called ‘foresight intelligence’. Since it’s rare that societies manage to mobilise around slow threats rather than immediate threats, there need to be new ways and mechanisms for greater cooperation between people, because we are not going to succeed as a species if we don’t work together.

They’d like to see the development of steady-state economics which would destroy the ‘fables such as ‘technological innovation will save us’’. They’d like to see natural scientists working together with social scientists to look at the dynamics of social movements, sustainability and equality and to scale up the places where that kind of work is already happening.

They point out that our current methods of governance are inadequate to meet the challenges we face and that we need to work with developing nations who are currently looking to reproduce the western nation’s ‘success’ of industrialisation, so that they can instead be leaders to the new economy, because playing catch up will lead to global collapse.

Do Drs. Ehrlich believe that we can avoid a global collapse of civilisation? They think we still can, but only if we get fully into gear and work together now, because unless we restructure our way of doing things, nature will do it for us. It’s your call humanity – shall we get going, or will we sleepwalk our species off the cliff?

Renewable Reality: Feasible and Inexpensive

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‘Aiming for 90% or more renewable energy in 2030 in order to achieve climate change targets of 80-90% reduction of CO2 from the power sector leads to economic savings, not costs.’

WHO: Cory Budischak, Department of Electrical and Computer Engineering, University of Delaware, Newark, Department of Energy Management, Delaware Technical Community College, Newark, USA
DeAnna Sewell, Heather Thomson, Dana E. Veron, Center for Carbon-Free Power Integration, School of Marine Science and Policy, College of Earth Ocean and Environment, University of Delaware, Newark, USA
Leon Mach, Energy and Environmental Policy Program, College of Engineering, University of Delaware, Newark, USA
Willett Kempton, Department of Electrical and Computer Engineering, University of Delaware, Newark, Center for Carbon-Free Power Integration, School of Marine Science and Policy, College of Earth Ocean and Environment, University of Delaware, Newark USA, Center for Electric Technology, DTU Elektro, Danmarks Tekniske Universitet, Lungby, Denmark

WHAT: Working out how you could power a region with renewable electricity and the cost of doing it

WHEN: 11 October 2012

WHERE: Journal of Power Sources, 225, 2013

TITLE: Cost-minimized combinations of wind power, solar power and electrochemical storage, powering the grid up to 99.9% of the time

This research from the US is quite practical. The researchers looked at the electricity use from 1999 – 2002 in the ‘PJM Interconnection’ which is a power grid in the North Eastern USA that includes Delaware, New Jersey, Pennsylvania, Virginia, West Virginia, Ohio and parts of Indiana, Illinois and Michigan.

They wanted to know what a renewable power grid would look like, how much it would cost and how you could do it. Research excitement!

The PJM Interconnection power grid area in the blue lines. Pink stars are the meteorological data sites (from paper)

The PJM Interconnection power grid area in the blue lines.
Pink stars are the meteorological data sites (from paper)

So what does a renewable power grid look like in this area? It involves a combination of renewables, which are onshore wind, offshore wind and solar in multiple locations which provides the greatest range of renewable power sources (if the wind is still in one state, it may be blowing in the next state).

The first hurdle this team had to jump was storage. The most popular storage model for renewables is wind-hydro hybrids (which I’ve written about previously here), however in this corner of the USA, there’s not much hydro power. So the paper looked at the options of electric vehicle grid storage, hydrogen storage and battery storage (lithium titanate batteries for those playing at home).

They used the data from 1999-2002 to model the hourly fluctuations of electricity demand, which averaged out at 31.5 Gigawatts (GW) of 72GW of generation. They then matched the load hour by hour with renewables and worked out which was cheapest.

They calculated the costs with a level playing field, which means no subsidies. No subsidies for renewables, but also a magical time when there’s not billions upon billions of dollars each year for fossil fuel subsides as well.

The results were that a renewable grid with 30% of coverage produced 50% of the power required for the sample years, while a renewable grid that provided 90% of the power coverage produced double the power required and a renewable grid that provided 99.9% of the power coverage produced three times the energy required. The researchers found that an overproduction of renewable electricity was preferable to trying to exactly match the power required and also reduced the need for storage.

A few of the benefits they found were that offshore wind and solar often generate when inland wind doesn’t, and that there was greater over-supply of power in the winter months which could allow for natural gas heating to be replaced by renewable electric heating.

Renewable power in the 99.9% model only needed fossil fuel back up 5 times in 4 years (from paper)

Renewable power in the 99.9% model only needed fossil fuel back up 5 times in 4 years (from paper)

What about the costs? The researchers looked at what the cost was for power in 2010 dollars and then adjusted for efficiencies to estimate the 2030 cost of power for the model and the infrastructure.

The 2010 cost of power was 17c per Kilowatt hour (kWh), while a renewable grid with 30% coverage would cost 10-11c per kWh, a 90% renewable grid would cost 6c per kWh and a 99.9% renewable grid is at parity with the fossil fuel grid at 17c per kWh.

The reason the 99.9% cost is higher than 90% is because filling the gap of that final 9.9% requires more infrastructure to further diversify the grid, but I think the most important thing they found in their research is this:

‘The second policy observation is that aiming for 90% or more renewable energy in 2030, in order to achieve climate change targets of 80%-90% reduction of CO2 from the power sector, leads to economic savings, not costs.’

Yes, even in coal country in the USA, switching to a hybrid renewable system (in a level playing field) is cheaper than the current cost of fossil fuel electricity. It also comes with the added benefits of no mercury poisoning from coal fired power plants too!

The paper concludes that while excess power generation in a renewable grid is a new idea, it shouldn’t be too problematic since it saves on storage needs and is the most cost-effective variation.

Their advice for plucky leaders who would like to make this grid a reality? The most cost-effective way to build this grid is to aim for 30% renewables now, and phase in the rest to 90% in 2030. Each step along the way to more renewable power will not only be a climate saving step, it will save money as well.

How Does Your Wind Farm Grow?

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Calculating what the global saturation point for wind energy would be and if we can generate enough wind power to power half the globe.

WHO: Mark Z. Jacobson (Department of Civil and Environmental Engineering, Stanford University, Stanford, CA)
Cristina L. Archer (College of Earth, Ocean, and Environment, University of Delaware, Newark, DE)

WHAT: Predicting the effectiveness of scaling up wind power to provide half the world’s power requirements by 2030.

WHEN:  September 25 2012 PNAS, Vol 109, No. 39

WHERE: Proceedings of the National Academy of Sciences of the United States of America

TITLE: Saturation wind power potential and its implications for wind energy

I learnt about a new law today; Betz’s Law. Betz was a guy who decided to calculate exactly how much energy could be extracted from the wind by a turbine at any given time mathematically (as you do). He worked out that no turbine can take any more than 59.3% of the energy from the wind. To be able to conceptualise this, you have to think about wind like a physicist. The first law of thermodynamics states that you can’t create or destroy energy; you can only convert it to different forms. Therefore, all wind is just energy in a certain form, and in any system there is a point where the transformation is most efficient and beyond there it takes a lot of effort to get any more energy from the system.

There’s a really cool project being done in the US, where a website has taken data from the National Digital Forecast Database and created a visual representation of what wind would look like if you could see it move. It’s strikingly beautiful, and looks a lot like a Van Gogh painting.

Wind Map by Fernanda Viegas and Martin Wattenberg of hint.fm

The question this paper looks at is: since there is a limit to the amount of energy you can take from a turbine, what is the maximum wind power that can be extracted from a geographical area? They called it the ‘Saturation Wind Power Potential’.

They came up with some interesting findings, as well as probably having a lot of fun along the way because they used 3D Models to do it (I’m telling you, my chemistry molecular model kit was much more like playing with Lego than actual ‘science’). They got into the detail and calculated the potential wind power at 10m off the ground, 100m off the ground (the standard height of a wind turbine) and 10km off the ground in the jet stream.

They then looked at whether it would be possible to scale up wind power globally to meet 50% of the world’s power needs by 2030. Actually measuring the wind power potential for more than 1 Terrawatt (TW) of energy is not possible as there isn’t enough wind power installed yet. But they did mathematically work out that we would need 4million 5 Megawatt (MW) turbines to supply half of the world’s electricity needs in 2030 (5.75TW).

They did four simulations with different turbine densities, because how close together wind turbines are affects their ability to produce power. Put them too close together and they start stealing their neighbour’s wind power. Overall, up to 715TW, the increased number of turbines increases the amount of power in a linear straight line. Once you get above that it slows down and flattens out – once again you need to put much more effort in to get power out.

Predicted wind power saturation potential (from paper)
Grey line – global wind power potential, black line – wind power potential on land only

The saturation point, where no matter how many more turbines you add, they’ll just be stealing energy from each other and not adding anything to the total, was 2,870TW of power globally. Interestingly, they found the wind power available in the jet stream (10km above the ground) was 150% greater than the wind power available 100m above the ground.

There were also some big changes to the results depending on the density. If we placed 4million 5MW turbines and packed them in at 11.3 Watts per m2 (W/m2), they would be too close together and the collected power wouldn’t match the target for half the world’s power by 2030. If you spread them out to 5.6W/m2 the output is still too low. However, once you’ve got them spaced at 2.9W/m2, they produce enough power to meet the required demand.

4million turbines meet demand when they’re 2.9W/m2 apart or further (from paper)

So it turns out wind turbines don’t like it when you cramp their style. But, you can pack them in a bit tighter, only if you then have enough space between your wind farm and your neighbour’s wind farm. It’s a bit like playing wind farm Tetris.

What does this mean though? It means that we can ramp up world wind power production to levels that will meet half our power needs in 2030, which can be integrated with hydro, solar and other renewables with smart grids to power our cities and lifestyles without burning fossil fuels. But it also means we need to think about where we are putting wind farms and how much space they need to be as efficient as possible. We need that renewable energy, so we can’t cramp the wind turbines’ style!

Renewable Hybrid Systems: Optimising Power Grids

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WHO: Robert Huva, Roger Dargaville and Simon Caine

WHAT: Electrical power grids powered by renewable energy

WHEN: Published in Energy [41 (2012) 326-334]. April 2012

WHERE:  Earth Sciences department, The University of Melbourne, Melbourne, Australia

TITLE:  Prototype large-scale renewable energy system optimisation for Victoria, Australia (subs required)

One of the major barriers to the full scale take-up of renewable energy to power electricity grids has been the need to provide baseload power to users. This is the power required to keep your fridge running through the night, the power to keep traffic lights running all day and night and many other things. It’s the minimum amount of electricity required to keep the modern world running.

Renewable power is not constant, because the sun doesn’t shine at night and it’s not always windy, and water runs through rivers at different speeds depending on the time of year. So in order to provide the constant power needed, a hybrid system of renewable energy sources needs to be used.

This paper from the University of Melbourne in Australia has done that. They used detailed weather maps for the state of Victoria to determine the best locations for solar and wind power.

Victoria, Australia (Google maps)

Best locations for wind (blue) and solar (red)

They then combined the outputs of the solar and the wind with other forms of renewable energy, including hydro-electricity (running water spinning a turbine to make power) and wind-hydro hybrids where excess wind power will pump water up a hill to a raised dam, and when the wind dies down, the dam gets opened and the hydro starts producing electricity.

They found that the entire electricity needs of the state of Victoria could be met from renewable power sources with only 2% back up from natural gas needed.

 Hybrid renewable systems – meeting demand

So what does this mean for reducing the effects of climate change?

It means that renewable power is viable in the state of Victoria, which will allow the state to switch from it’s current power source of brown coal (which is much dirtier than your standard black coal when it burns, releasing more carbon pollution into the atmosphere).

Making the transition to a hybrid renewable system will also significantly reduce carbon emissions in the state of Victoria since 49% of energy in the state comes from coal power. It will create a large number of new jobs, as the renewable energy market increases from 12% (in 2011) to the 98% that has been shown in the research, which we will need to do in the next 30 years if we want to avoid catastrophic climate change.

How can it be done? By ensuring areas are able to access either localised power production (in rural or remote areas), or smart grids (in cities) that are able to monitor and respond to changing power production levels and changing energy use levels, hybrid systems of renewable electricity are fully capable of providing the power we need to run our lives.

*Full disclosure: The name is not a coincidence – this research was conducted by my brother as part of his PhD research (yes, I’m using my brother’s research to test out my own blog 🙂 )