This Beam Op-Ed is part of a series highlighting the sectors where current practices and technologies are major sources of greenhouse gas emissions, and how we can change the status quo with new technological solutions.
You can think of the emissions contributing to climate change on Earth as having several different flavors. They come from these major categories: electricity usage, transportation, and industrial emissions from sources like agriculture and manufacturing. Together, they make one massive sh*t sandwich. Today, we address how our sources of power affect global carbon emissions, and the paths we can take to make sure we reduce the influence of electricity on climate change.
Generating the electrons that power everything in our plugged-in world is the most obvious source of climate changing greenhouse gases. It’s also one of the biggest contributors to CO2 emissions, making up 35% of total energy-related carbon emissions in the United States in 2017. If we can make electricity generation fully renewable, we could make substantial progress in avoiding our current crash course trajectory into catastrophic, irreversible impacts of climate change.
Let’s set a frame of reference: you should think about CO2 emissions in terms of Gigatons. We spew 33,400 million tonnes (33.4 Gigatons) into the air every year, and has caused a rise in CO2 concentration in the world’s atmosphere to a record-breaking 410 ppm.
This is more than at any time over the last 800,000 years. This is bad.
How electricity relates to emissions — and where we are at globally
We use a LOT of electricity in the United States. In 2017, the average American household consumed over 10,000 kWh of electricity on it’s own. This is substantially more than households in other countries. Globally, the average is 3,100 kWh. Yikes.
The sheer amount of electricity our world requires is one huge piece of the issue. Every year the world uses tens of thousands of Terawatt-hours (TWh) of electricity. For reference, a TWh equals one trillion watt hours. In 2018, the globe consumed 20,000,000,000,000 Wh of electricity. Aka a lot. Point made, get on with it, we know.
The second piece is that all of those electrons have to come from somewhere, y’all. The human species realized eons ago that the combustion reaction that is fire would provide life-giving sustenance, and up until very recently we have relied on it almost exclusively to give us energy, whether it’s in the form of warmth or power. We have been blowing stuff up for centuries to give us the energy we need. Electricity has been no exception.
Traditionally, electricity providers did not have to think about sustainability of how they sourced electricity. They just had to provide it — and make sure it was always available. Reliability is a constant guiding principle for electrical utilities, and this is why, when you flip a switch, you expect it to work every time.
For example, throughout the 20th century, coal has played a major role as a primary generation source for electric power — in spite of our collective long-standing knowledge of coal’s horrible environmental and health impacts. Even today, fossil fuels account for over 60% of global electricity generation.
We used the U.S. as an example here, but the problem spans the globe. In fact, because of the rapid growth in electricity demand in Asia and particularly China, the world hasn’t been able to drop below that 60% number for decades.
In sum: we use a great deal of electricity to power our lives, and we have been — and are still — relying way too heavily on fossil fuels for that electricity.
Renewable electricity is here — here’s what we need to ramp it’s adoption
Our climate problem is serious, but renewable electricity generation provides us with a way forward. From an emissions standpoint, renewables are far preferable to fossil fuels because their life cycle emissions are nearly zero (this metric considers all of the energy used in relation to a technology). Once installed and operational, these resources use no fossil fuels and emit zero greenhouse gas. Renewables are superior to our traditional combustion-based tactics for another reason, too: their cost. Renewables have very low to zero operational costs, and fossil fuels can’t compete with that when bidding to provide electricity to customers.
For this second reason especially, renewable power generation is set to outcompete fossil fuels. Increasingly, renewables are just good business.That’s great, right?! However, there are a few technical issues that have been slowing down that transition just when we can’t afford a slower rate of adoption.
Energy storage is part of the answer
To accelerate the adoption of renewable electricity, we have to address the very real mismatch between our expectation of reliability and the intermittent nature of solar and wind. Energy storage is a critical piece of a renewable electricity solution because it can hold onto electrons generated by renewables until we need them, effectively transforming them into constant resources we can always tap into.
Think about energy storage in this way: it’s anything that allows us to hold onto electrical energy for as long as we need to, and then, when it’s time, to release that energy as fast as necessary, all without losing any of that stored energy in the process.
There are many types of energy storage, some of them downright basic, relying on moving air and water, for example (see a list here). Batteries are regarded as a game changer for renewable electricity adoption because of they are reliable, can be replicated in many places, and can provide the right level of energy or power needed for a given application. Lithium-ion batteries are the state of the art when it comes to energy density, or energy storage per unit volume, they can store. Versions of the technology appear in smartphones and electronic devices, electric vehicles, AND in grid-level energy storage, all of which have different requirements for how much power and energy are needed.
But as we explained in our first op-ed, lithium technologies have their drawbacks. One of them is the cost; others include limits in supply and ethical issues associated with mining the materials needed. There are also a high maintenance technology: a battery management system is needed to keep Li-ion batteries in a suitable temperature range, because they do really poorly in the cold; there are safety issues (lithium is extremely reactive — who can forget the fateful Samsung Galaxy Note 7, which failed because the barrier between reactive layers in the battery was thin enough to degrade and cause an explosion?); there are lifetime issues (who here can honestly say they haven’t experienced a rapidly dying phone battery before?). Finally, and critically, there is a limit on how much energy per space you can store with all types of batteries. If you want more power, you need to be willing to accept the extra space, weight, and cost of additional batteries added to a bank — let’s call this the “lego issue”.
There are ways to address the safety, lifespan and performance issues, through the development of new battery materials. The lego issue, on the other hand, can be solved by other technology platforms that are similar to batteries, but which decouple the reactive chemicals from the energy storage unit. These include fuel cells, which might be thought of as batteries that run on fuels pumped into the cell; and flow batteries, which store the electrolytes of the battery in tanks outside of the electrochemical cell (= battery), that then flow into the cell to store or release energy. In both cases, to store more energy, you don’t need a bigger cell, just the right amount of fuel on hand.
Flow batteries and fuel cells both complement and compete with batteries by providing storage in situations where batteries are untenable or cause issues. One good example of this is the use of fuel cells in forklifts at Walmarts and Costcos (a real thing), because they can be filled up with fuel in minutes and can use more of the fuel, with no loss in power, before needing to be fueled again. Flow batteries are promising for use as grid storage units, and university research groups, startups, and large companies alike are working on solutions to make them commercially viable. Startups especially in this space have the flexibility to bring innovative university technologies to the level of development a large company could scale and deploy, and so it is important to help them accelerate their progress.
All of the above
Developing all three technologies — flow batteries, traditional batteries and fuel cells — will make energy storage possible and cost-effective in a whole slew of applications like this one. In fact, the more energy storage solutions we pursue aggressively, the faster we can support the transformation of the electrical grid to 100% clean. This applies, too, to technologies that allow us to be more energy efficient and to match renewable electricity supply to the varying demand for power. In all cases, diversifying over a portfolio of new technologies means managing the risks and unforeseen issues that come from deploying new innovations. We can’t afford to put all our eggs in one basket, nor can we settle for current state of technology and deployment.