Can California really be carbon-free by 2045?

Solar panels on the roof of the Los Angeles Convention Center. Image: Getty.

California governor Jerry Brown recently signed a new law mandating that the electricity the state consumes not cause carbon emissions by 2045.

He also issued an executive order that goes even further: it commits California to “achieve carbon neutrality” across the board and not just for power generation by 2045. Together, these steps codify California’s ongoing transition away from relying on fossil fuels for energy. This effort has been ramping up since 2011, when Brown signed another law committing the state to deriving a third of its energy from renewable sources like wind and solar power by 2020 – not including big hydroelectric dams.

Based on more than 30 years of research related to solar energy, by my assessment, California can meet the law’s ambitious goal as long as it continues to implement programs that encourage the rapid expansion of renewable energy in the state.

A growth industry

The new law actually sets multiple targets rather than just one. It commits California to draw half its electricity from renewable sources by 2026, a share that would rise to 60 per cent by 2030.

To take the next step, rather than mandating that all power be renewably sourced, state lawmakers established a 100 per cent “zero-carbon” goal. They did not define this term, but it is understood as including wind and solar power, big hydropower plants and other sources of electricity that do not generate carbon dioxide.

Utility-scale solar and wind electricity increased from 3 per cent in 2010 to 18 per cent in 2017 in California, exceeding prior state targets, largely because solar prices have dropped sharply in recent years.

Being open to a wide range of technologies makes meeting the 2045 target easier and allowed State Senator Kevin de Leon, the original bill’s author, to amass broad support for the bill.

Where things stood in 2017

About 56 per cent of the power California generated in 2017 came from sources that don’t emit carbon. That puts it more than halfway toward this new goal by 2045.

However, the Diablo Canyon plant, California’s last nuclear power station, is slated for decommissioning by 2025, and no other reactors are in the works. This closure would eliminate the 8.7 per cent of the state’s carbon-free power that came from nuclear energy.

Nearly all of the remaining 44 per cent of the state’s electricity is currently generated by burning natural gas, and virtually none comes from coal. Going completely zero-carbon would require phasing out the state’s natural gas power plants.

On top of wind and solar energy, other generation options include geothermal, small nuclear reactors and carbon dioxide sequestration.

One quirk about this legislation is that it deals only with utility-scale power. It would not preclude private electricity-generation facilities such as the diesel generator a farmer might use to pump water. Nor would it count the power generated by a homeowner’s rooftop solar panels.

When the sun shines

One complication is that the state’s mix of energy sources can vary a great deal, even from one hour to the next.

Consider what happened on 8 April 2018, for example. It was a generally sunny and windy Sunday, with relatively low electricity demand. At night, about 40 per cent of electricity was generated from renewable sources. But around noon that day, more than 80 per cent came from renewable sources including large-scale hydropower.

If the electricity generated from these renewable sources is approximately doubled, as I estimate is necessary to meet the 2045 target, the power available in the middle of the day would greatly exceed the demand for electricity at that time.

This challenge shifts throughout the year.

On 24 and 25 July, Californians were asked to voluntarily use less electricity between 5 p.m. and 9 p.m. to avoid an outage because of hot weather. Prices spiked by more than a factor of 10, helping to keep demand within the supply.

On those days, renewably sourced electricity never met half of the demand for power.

Balancing act

Due to this degree of variability, relying heavily on renewable energy will require ample energy storage and big investments in grid-based technology.

Today, the expected demand for electricity is balanced by the Independent System Operator, an entity that controls the flow of electricity on the grid and selects the lowest-priced sources of electricity available.

Pumped hydro storage, electricity generated from water pumped to a reservoir, is the state’s most common form of storage today. While limited to locations with large dams, the amount of energy stored this way could be increased in California, as recently proposed for Hoover Dam.

Big lithium ion batteries are becoming more affordable and are now beginning to be deployed on the utility scale. As battery and solar prices drop, it may become attractive to disconnect from the grid and use electricity generated by a solar system and stored by a battery.

Lower battery costs are also spurring the sales of more electric vehicles. Ideally, these vehicles could be charged at times when electricity is plentiful and cheap. By 2045, I believe they could be helping make the grid more stable.

Other options are becoming available. One example is utility-scale compressed air storage, where energy is stored as pressurised air.

And there is growing interest in solar thermal plants, which generate electricity from sunlight’s heat and use high-temperature storage to continue generating electricity after the sun sets.

The University of California Merced and many other wholesale electricity customers are saving money by using thermal storage. They chill water when rates are low and use the chilled water for air conditioning when electricity prices are high.


Wiggle room

Because California’s new law does not require that every watt be generated within California’s borders, utilities could keep buying electricity from nearby states, as long as they verify its origins are in keeping with the new law’s requirements.

And because the law does not define “zero-carbon,” it provides flexibility in how the state can meet this new target.

For example, California would allow the continued operation of natural gas plants when their output is coupled with purchase of renewable energy certificates, credits issued for the generation of renewable electricity that may be sold, from a utility that generates solar or wind power.

These credits arise through several kinds of arrangements. Perhaps the most common is through rooftop solar systems. Small-scale solar energy supplied about 5 per cent of California’s electricity in 2017. It is likely to grow because of California’s mandate for solar panels on most new homes, starting in 2020.

In assessing whether the goal of going zero-carbon by 2045 is realistic or not, it is worth considering that solar energy has grown for years at a pace that far exceeded projections: thanks to technological progress, government policies like California’s new law, market forces and the public’s demand for renewable energy.

The Conversation

Sarah Kurtz, Professor of Materials Science and Engineering, University of California, Merced.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 
 
 
 

Why is it acceptable to kill someone? On the mysterious history of Britain’s road death toll

A London speed camera, 2004. Image: Getty.

A decade ago I became fascinated by a graph. This one:

I had been tracking the underlining data for years. The figures were easy to remember. Every year it was 3,500, plus or minus a percentage point or two.

Yet when the 2008 data was released, it had fallen to 2,538. This was 1,000 less than the figure in 2003. I plotted the above graph, and as I said, I became fascinated.

Because this is a really important graph. This is a plot of the number of people killed on Britain’s roads each year.

In Great Britain, collectively, we used to kill nearly 3,500 people on our roads every year. Consistently or, dare I say it, boringly: 3,500 deaths a year, 10 a day. It was accepted, in a, “Well yes it’s bad, but what can you do about it” kind of way. There was no clamour for change. Newspapers weren’t running headlines about the deaths mounting up, as they do with knife crime.

Meanwhile a train crash would be front page news for a week. Take the train that derailed at Hatfield on 17 October 2000, a tragedy in which 4 people died. That led to huge media interest, massive upheaval on the railways, and, ultimately, as the re-nationalisation of Railtrack, whose failings had caused the crash. Yet more than twice as many people will have died on the roads that day. Nothing was written about those deaths. Nothing changed.

In 2000, four people died in train crashes, while 3,409 died on the roads.

Here are those figures again.

1997 – 3,599 people killed on our roads

1998 – 3,422

1999 – 3,423

2000 – 3,409

2001 – 3,450

2002 – 3,431

2003 – 3508

But, in 2004 the figure dropped below 3,400 for the first time, to 3,221. Then in 2005 to 3,201.

2006 – 3,172

2007 – 2,946

Below 3,000! This was change. Significant change: 500 lives a year were not being lost. If you use Britain’s roads, your life may have been one of them.

2008 – 2,538

2009 – 2,222

When the 2010 figures came out I was amazed by the headline figure: 1,857.

That’s still far too high, of course, but it was 1,701 lower than seven years earlier.

This was a major story that deserved a ton of coverage, which it failed to get. Having shown no concern for when we were killing 3,500 people, it wasn’t overly surprising that the fact we were now killing 1,700 fewer wasn’t celebrated.

At any rate, the graph had flat-lined for years, then, in half a dozen years, it halved. Why?

The lack of media coverage resulted in an absence of answers. One commentator, Christian Woolmar, observed that there was no clear answer to why this had happened. But he went on to point out that there had been a fall in the average road speed over this period.

My anticipation of the 2011 figures troubled me, because I expected them to go up. Obviously I didn’t want them to: I desperately want zero deaths on our roads. But something happened in 2010 that I was sure would lead to more fatalities and bring a halt to the falling trend.

I was right. In 2011 we killed 1,901.

Sometimes, being right is shit.

The news was better in 2012. The fatality rate was 1,754. So was the 2011 figure just a blip, due to some significant snowfalls that year? No: the trend was over.

The number of people killed on our roads has remained stuck in the 17 hundreds. 

2013 – 1,713

2014 – 1,775

2015 – 1,732

2016 – 1,792

2017 – 1,793

2018 – 1,782

We have returned to a flatline on the graph – and if anything, I’m more fascinated now than I was before. Road deaths flatlined at 3,500 for years, then fell sharply, then flatlined again at half the rate.

This can’t have happened by accident. I wished I could explain it. I wish we could repeat it. No: I wish the second flatline hadn’t happened, and the fall had continued. If the rate of fall had continued, we’d have reached zero deaths on the road by now. You’d be right to question whether this is possible – but if you can half the number in a few years, why can’t we eradicate them altogether? The railways are an example of what is possible. The last time a passenger died in a train crash on Britain’s railways was in 2007.

It was time to figure out the answers to two questions. Why did the death toll fall? And why did it stop falling?

The obvious reason for a reduction in deaths on the road is the improvement in car safety features. This could create a gradual fall in the death toll as new, safer cars replaced older ones. But I’m not sure it can explain a 40 per cent fall over a 4 year period.

There’s a way to check whether cars on the road became almost twice as safe between 2003 and 2010: you can compare the figures with the rest of the EU. Car safety features are international, and any new feature would have appeared around the same time across the continent.

So I found the EU figures for 2000 to 2017, indexed for 2000 and plotted the graph for multiple countries. It was a busy graph. For clarity the following graph only includes Britain, Germany, France, Spain and Italy along with a straight line drop for comparison.

The good news is that things are improving across Europe – but no country had quite the same trajectory as Britain. They all have a fall much closer to a straight line of the sort you’d expect a general improvement in car safety would produce.

One thing I did notice is that, from 2013, these five countries stop falling. The technology based solutions of recent years, such as automatic emergency braking, don’t appear to be saving lives as of yet.

So, yes, cars are safer – but that doesn’t seem to explain why British roads suddenly became 40 per cent safer between 2006 and 2010.


In 1999, the New Labour government announced that it was going to reduce deaths on our roads. The target was a 50 per cent reduction by 2010. As you now know, it succeeded. This was a major achievement for a government. The kind of thing you would bang on about all the time. “Deaths on our roads halved by Labour!” But the party wasn’t in government when the 2010 figures were released – and it’s hard to take credit for your achievements from the opposition benches.

That it was government policy is not a full explanation, and how this happened is a little opaque. From what I can gather there was a wide ranging approach. The fire and rescue service changed their practices: because they recognised that survival rates were directly dependent on how quickly people got to hospital, this became the priority. Disturbing a police crime scene was allowed if it saved a life. Accident black spots were located, highlighted and safety measures implemented. Throughout that period road safety campaigns focused on speed, with “Speed Kills” being the dominate message for that decade. The government also changed the laws on speed cameras.

RoSPA, the Royal Society for the Prevention of Accidents, has a lot to say about speeding and speed cameras. Its “Speed Camera Factsheet” states that, “Cameras are a very effective way of persuading drivers not to speed, and thereby reducing the number of people killed and seriously injured.” It reports that an independent review published by the Department for Transport (DfT) in 2005 said that “cameras significantly reduce speeding and collisions, and cut deaths and serious injuries at camera sites”, adding that cameras sites were delivering 100 fewer deaths per year.

Cameras first appeared in 1991, and revenue from court fines and fixed penalties went to the Exchequer. However in 2000 a trial scheme saw local councils keep the fines to pay for the cost of speed and red-light cameras. The pilot was so successful that, in 2001, legislation enabled this to happen across the country. The cost of providing and operating cameras moved from the local authority to the law breaking motorist.

The golden age of the speed camera had begun.

There was a tweak to this legislation in 2007. Fines reverted back to the Exchequer’s piggy bank. The DfT switched to funding cameras through a road safety grant. The intention was to create a greater mix of road safety measures agreed between local authorities and the police.

The number of people killed on British roads in 2007: 2,946

The number of people killed on British roads in 2010: 1,857

So perhaps the creation of the Road Safety Grant had a significant impact.

The second question: why did the death toll stop falling?

In 2010 I was unaware of Labour’s target to halve deaths on the roads. But, the change in government was enough for me to predict that the fall was over.

When the Tory/Lib Dem government negotiated its way into power in May 2010, the press declared that it was the end of the horrible nanny state – a return to personal freedom, liberty and the rule of common sense.

The way that this was to play out in real practical terms was on our roads. The evil speed camera was in the firing line. The narrative was that these cameras were just there so councils could extract cash from the poor public. Completely ignored were the facts that the fines were only handed down to dangerous, law-breaking drivers, and that councils no longer got the cash from fines.

Soon after the election the coalition government said that “Labour's 13-year war on the motorist is over” and pledged to scrap public funding for speed cameras. The Road Safety Grant to local authorities was cut from £95m to £57m. This meant that the government was now receiving an estimated £40m more raised in fines than it was spending on road safety. The cut to the grant reduced the camera maintenance budget by 27 per cent. It removed all the funding for new cameras, speed humps and other safety measures.

And the golden age ended.

Councils across the country announced their change of policy. Oxfordshire County Council switched off its speed cameras on 1 August 2010. Money was saved; lives were lost.

Eight months later, on 1 April, Oxfordshire’s cameras snapped back into life when the council reversed its decision because deaths on the county’s roads had immediately increased.

Turning off speed cameras sent out the message that we were no longer taking speeding seriously. The road safety campaigns changed their focus. The message that Speed Kills fell away and was replaced by drink- and drug-driving messages. It’s easy to miss that these campaigns move from encompassing virtually every driver to targeting a minority. A switch from confronting a socially acceptable behaviour to re-enforcing something already unacceptable. The state is no longer challenging everyone to be safe – only the small minority of bad people.

Yet speed still kills. The World Health Organisation states that an increase in average speed of 1 km[h typically results in a 3 per cent higher risk of a crash involving injury, with a 4–5 per cent increase for crashes that result in fatalities.
The majority of safety measures installed before 2010 remain in place and are saving lives. But with the funding gone councils are no longer installing new measures and the death toll is no longer falling.

So you can make a strong case that the pattern of road deaths was the result of government policy.

Which begs the question of our government: why has it accepted that it’s OK to kill, or be killed, on our roads?