George Minter on Natural Gas’ Foundational Role in a 100% Clean Energy Economy

George Minter: Today, energy, and how we use it, is center stage. That’s because its use generates emissions that contribute to air pollution and climate change. And California is the world’s leader in addressing these critical environmental issues. 

California’s focus has been on a 100% clean energy future—a renewable energy future. That’s where we need to go. But we often only talk about electricity—making electricity renewable by promoting the development of solar, and wind, and other renewable electric generating resources. And then we expect everything will run on electricity.

But that’s a narrow view of the future. For tomorrow, we must think more broadly. A focus on only one source of energy may not be realistic, nor have the best outcomes. We use a lot more than just electricity. We use all kinds of energy resources in transportation, in our businesses and industry, and every day in our homes.

Most of us are still driving gasoline cars and diesel trucks. Trains, planes and ships still run on petroleum fuels. Big commercial and industrial operations use fuels to meet thermal needs and to run large industrial processes. And, in southern California, over 90% of residents, every day, rely on natural gas to heat their homes, their water, or to cook their food.

Sure, we light our world with electricity, and a lot of gizmos run on it. Even our passenger cars and light duty trucks will be running on it in time. But a more holistic approach to developing renewable energy means we must look to all of our energy resources, and reasonably balance which energy is best for which end use – and drive down emissions, and drive toward renewable sources.

We must replace dirty fuels with clean fuels, and depletable fuels with renewable fuels, and we must do it efficiently, cost effectively and with the lowest emissions outcome. It turns out that many of these fuels can be renewable too. Even the gas we use in our homes can be renewable, just like electricity can be.

Capturing methane gas from our waste streams—like waste water treatment, landfills, dairies and agricultural operations—becomes a renewable energy resource. When processed, biogas can replace fossil gas. In fact, the California Air Resources Board has adopted an aggressive Short Lived Climate Pollutant plan (in conjunction with the legislature passing a law) requiring 40% capture of methane from the state’s waste sources.

So what do we do after we capture it? We put it into gas utility pipelines and deliver it to customers as renewable gas—driving down the carbon content, and the climate changing impact, of gas end uses. This is happening all over the world, and California is just getting started. Today, renewable gas is moving into the transportation sector.

In Southern California, most transit agencies already have switched from diesel to natural gas engines, and are now purchasing a new 90% lower emitting “near zero” engine. This is a newly developed engine for transit buses, waste haulers, and public fleets that has attained so low an emissions level that the state’s air agency has certified it as “near zero,” approaching the emissions associated with generating electricity to run that vehicle as an electric one. It reduces air pollution emissions by over 90%, and it’s on the road today.

This is a big deal, a gamechanger, because it turns out that in the Southern California region and also the San Joaquin Valley (the two areas of the state with the worst air pollution), most of the polluting emissions come from the transportation sector – over 80%. And the single biggest contributor of polluting emissions is heavy-duty transportation – like trucks and buses.

Today bus and trucking fleets are looking to adopt this new engine, and fuel it on renewable gas. The state’s new Low Carbon Fuel Standard program has created an economic incentive to purchase renewable gas for transportation use, and now the gas they run on is over 60% renewable – and growing!

This means these vehicles are way ahead of the game in terms of renewable energy. California’s very strict climate change rules require electricity to be 33% renewable by 2020, and 50% renewable by 2030. But these buses and trucks are already past that mark—putting less pollutants and greenhouse gases into the air.

As more demand for renewable fuels in the transportation sector develops over—and we’re seeing this happen now—then more renewable fuels like renewable gas will be developed and become available to be directed to everyday uses like home heating, water heating, cooking, and even commercial and industrial uses.  This approach to reducing the carbon intensity of everyday energy use avoids the very difficult and costly approach of requiring homeowners and business owners to switch out gas appliances for electric ones.

It also turns out that the direct end us of gas, particularly for thermal uses, is often more efficient, with lower emissions, than using the same kind of electric appliance. One study shows that until the electric grid is over 50% renewable, a natural gas appliance still produces less emissions than an electric one. But by 2030—when the state’s goal is to reach 50% renewable electricity—renewable gas can be providing the emissions benefit for home heating and cooking uses, efficiently and cost effectively. 

In fact, this same study documented that a mixed approach to both electrification and low carbon gas supply would be the least risky, likely lowest cost, and ultimately best pathway to achieving California’s climate change and air quality goals. It concluded that we should direct increasingly renewable electricity to light duty transportation sectors, while deploying natural gas and renewable gas to heavy-duty transportation using near zero combustion technology. And over time, as the renewable gas portfolio develops, direct its low carbon characteristics to core gas uses.

We also know that we will need all kinds of energy storage technologies so we have electricity when the sun doesn’t shine or the wind doesn’t blow. We already have petroleum and gas storage for when demand skyrockets. Petroleum is stored at refineries and also in underground tanks at gas stations and other facilities all throughout our cities, towns and roadways. Natural gas, in California, is stored underground in depleted oil reservoirs which held oil and gas in the first place. Storage of gas enables its delivery when it gets cold, for example, and when demand for gas exceeds supplies able to come into the state over pipelines.

Many people don’t realize that most natural gas comes from out of state through large pipelines, and that as a molecule, unlike electricity, it doesn’t travel very fast, only about 35 mph. That means it would take 8 hours for gas from the border to get to the demand centers when supply is needed to power air conditioning on hot summer nights or to heat our homes and classrooms on cold winter days. No one can wait that long. 

For electricity, however, we are just beginning to develop our storage capacity. Today we are focused on battery storage, and pumped hydro, and other storage technologies. But tomorrow we will be looking at hydrogen as a renewable energy resource—and a resource than can actually store renewable electricity.

Ironically today California is experiencing an oversupply of renewable energy—particularly solar in the middle of the day when it is at its peak, but most folks are at work. That energy has to be prevented from going onto the grid, essentially wasted, in order to keep our grid balanced and protected.

Throughout Europe today companies are building and operating new “Power to Gas” facilities, or P2G, which directs that excess renewable energy off the grid into an electrolysis facility—essentially running electricity through water (H2O) to produce H2 gas and O2 gas. H2 gas is an energy carrier and can be deployed directly to transportation as a renewable hydrogen fuel for fuel cell powered transportation, or other equipment. It can also be blended into the existing gas grid to reduce the carbon content of delivered natural gas. And in another common industrial gas process – an air shift reaction (or Sabatier reaction) the hydrogen can be combined with captured carbon dioxide to produce renewable methane—just like the natural gas and biomethane that is in the pipeline system.

This renewable gas also can be stored in existing facilities for later use, and then be deployed for thermal applications for household use or even to generate power when needed. Scientists advise that transforming electrical energy into molecular energy enables storage without loses over time, as well as storage in large volumes, greater than that afforded by the electric grid or batteries.

Now, many people ask, why would we want to rely on a dirty fossil fuel like natural gas, even if it gets renewable over time, just like electricity is? Shouldn’t we just eliminate all the pipelines and gas end uses and just rely on electricity?

One of the lessons the recent hurricanes has taught us is that infrastructure resiliency is important, and having an integrated energy grid will enable us to deliver different forms of energy under different circumstances. In Houston, hospitals and industrial facilities that had their own combined heat and power systems were able to operate and provide needed medical attention, when the electric grid went down, because they had their own heat and power provided by gas pipelines. In one case, a large chemical plant, which experienced a series of industrial accidents when its power failed, could not control some of its processes, resulting in fire, because it did not have such a capability.

A few years ago when hurricane Sandy affected the east coast, and power was lost to millions, there was still light and heat in a number of facilities that ran on fuels cells powered by natural gas.

The science of climate change, mitigation and adaptation tells us we will need an integrated energy grid with both electric lines and gas pipelines to manage our energy delivery needs as we move into the future. Our clean energy future will require us all to work together to develop renewable forms of all our energy resources, and deploy them to the best use with the best outcomes.

As for today’s natural gas, let’s recall that we all rely on this lower cost energy resource during our day at home, at school, in business and industry. Natural gas is a low emission energy resource when compared to both coal and oil. Today natural gas is cleaning the air and reducing climate change emissions by replacing coal in the Midwest for electric generation, and fuel oil in the east for heating. That’s a good thing.

Here in California we have already done most of that. Gas has already replaced coal as a generating resource, except for the coal generation from out of state still relied upon by some municipal utilities. Natural gas power generation also helps more and more renewable resources like solar and wind get onto the grid. When the sun doesn’t shine or the wind doesn’t blow we rely on gas to keep the lights on. In fact, over half of the actual generation of electricity in California is still natural gas.

But things are changing, of course. We are not going to be relying on big natural gas base load power plants in the future. What are developing are smaller scale peaking generators that can ramp up and down quickly to manage the intermittency of renewable power sources.

New gas technologies like the fuel cell, which provide both heat and power with no emissions, are also helping us to reduce our reliance on central generation. And as they become fueled by renewable gas, they will become another important source of 100% clean and renewable energy.

While buses and trucks are running on natural gas and renewable gas today, tomorrow rail and shipping companies will be looking to natural gas to displace diesel and bunker fuel to meet clean air, climate change and clean energy demands.

Finally, while over 90% of southern California residents and businesses rely on natural gas everyday also remember that natural gas almost entirely fuels our nighttime economy—providing the sundown power for our music, movies, TV and video entertainment. Also, it provides the fuel for our kitchens and restaurants. The nighttime economy is an important financial driver for the Los Angeles region. 

The air quality and climate challenges to our future energy use are big. And the energy industry will need to use all the tools in its toolbox to manage our transition to a clean energy future. Working together, making the best decisions, we will get there.