Power grids for a sustainable world
Electrification has played a prominent role in the development of modern societies in the past century. Some institutions such as the National Academy of Engineering acknowledge it as the number one engineering achievement of the 20th century (http://www.greatachievements.org/) . Electricity has now become a commodity, and power grids transporting electricity across states, countries, and continents are essential components of modern societies. Such grids play a central economical and societal role by supplying reliable power to industry, services, and consumers. Electrical transmission is not a simple task, however, and requires 24/7 monitoring and control of the grid to avoid electricity blackouts, which can lead to significant losses and delay in public services and strategical industries. Grid operators are skilled engineers, in charge of ensuring that a reliable supply of electricity is provided everywhere and at all times. As surprising as it may be, their task is becoming increasingly difficult in the digital era because efforts made to automate operation are insufficient and they have to constantly examine massive amounts of data in real-time. In the face of a resurgence of blackouts in modern but aging grids (California, New York, Australia, The UK in 2019), new developments are becoming urgent to keep operating robust grids. Electricity should be a reliable commodity, especially for those in less densely populated areas with more difficult access to public services.
Power systems are in some sense archaic, while complex, ``artificially intelligent'' systems currently in operation, and they are in great need of 21st century innovation to manage the increasingly complex task of satisfying electricity demand, all while using renewable energies and opening market exchanges. Renewable sources such as wind and solar are intermittent sources of energy due to their dependence on meteorological conditions. Also, while providing opportunities for exchange, electricity markets bring in their own variability and uncertainties in the system. As with most national power grid operators, the French national grid operator, Réseau de Transport d’Électricité (RTE), is undergoing rapid and profound changes under a steep energy transition. This places new flexibility and reactivity requirements on the smart grids of the future. Adaptability is key for the power grid to fully reach its potential in mitigating climate change by allowing for total de-carbonization of our energy system, doing this under a sustainable approach with as little new infrastructure footprint as possible.
Robustness in power grids
A power system can be damaged under many different causes (storms, heat or cold, cyberattacks, human error). Often, this leads to power lines being out of service for few hours or days. Nevertheless, the system should still operate properly to ensure the proper transportation of electricity, especially when it is sometimes most needed after a storm. Hence, we need a resilient power system. In particular, it should be robust to the lost of any few lines at every moment.
20 years ago in december 1999, while we were all afraid of the 2000's bug in every computer, the problem didn't come as a digital bug in France but rather from a natural phenomena as 2 successive giant storms within 2 days!
Many towers were dramatically torn apart, many power lines were out of service, as you can see below. But the teams managed to still operate properly the power grid as they were prepared for a harmful event. Even if some households did not get electricity for few days, the grid was suprisingly quick to recover from such an event: it was resilient.
We should not forget to take into account nowadays this key property of a performant power grid.
A power grid tower torn apart in 1999 in France after 2 big storms in 2 days
A new challenge in 2020 will address part of this real-world important issue for critical power systems
Adaptability in power grids
Towards a Great Share of Renewable Energy
In the future, a greater share of renewable energy, that is wind and solar power, will help us transition toward a more sustainable world with fewer green house emissions. This however comes with new challenges to still ensure the reliable delivery of electricity 24/7.
Indeed today's power plant production mainly has to follow the demand with a risk of not meeting the peak demand called underproduction.
But tomorrow they will need to meet the net demand (demand minus renewable production). While demand is quite predictable today, the net demand will be more uncertain given the high variability of wind. In addition, solar power only produces during daily hours and induces a now well-known duck curve in net demand, introducing new dips and peaks in the net demand curve, with a new risk of overproduction. Faster power plants and more flexibilities will be needed to adapt and effectively continue operating the grid.
Powering the next 100 years - John Platt keynote at NeurIPS 2017
John Platt from Google explain very clearly as well the challenge of integrating more renewable. While he deems them as a necessary component, he demonstrates that we cannot rely on renewables only to reliably deliver the amount of energy we need. A complementary component needs to compensate for their intermittency and lower reliability. Otherwise, this would create a lot of over capacity installed of wind farms and solar panels coming with a huge footprint to produce them. He further advocates that fusion energy is the right research avenue to pursue to succeed in our sustainable energy transition. While this is not the only potential solution, this is one more exemple showing that the grid will have to adapt in the future.
To be completed
- French scenarios
- Less grid development
Climate attributable reductions to transmission capacity by decade (from top left to bottom right: 2020, 2040, 2060, 2080). Colors indicate the percent reduction in transmission capacity under the average RCP 4.5 scenario, relative to the 1990–2010 reference period. For additional information see "Impacts of rising air temperatures on electric transmission ampacity and peak electricity load in the United States" here.