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Building The Clean Energy Grid

21 October 2014

The scientific evidence is now overwhelming that anthropogenic climate change is not just something that will impact us in the future, but it is causing economic losses, social disruption, and political instability today. While recent events like Hurricanes Katrina and Sandy, and Typhoon Haiyan have brought the costs into sharper focus, the research community has seen this coming for much longer.  As the largest economy with the largest national research and development portfolio, the U.S. must help lead the transformation to a clean energy future and a healthier world. As we experience more intense and longer heat waves, prolonged drought, crop failures, rising seas, increasing wildfires and floods, we will see profoundly destabilizing effects ripple throughout our interconnected world.

Global warming already directly impacts public health, our economy, food and water supplies, and national security.  The scientific debate about whether human-caused global warming exists is long over. The remaining window of time for the needed transformation is short, and the only real issue is how do we respond.  This is where U. S. leadership has always been most critical, and where it must be again.

How can we be most cost effective in developing an energy infrastructure that meets performance, reliability, and robustness goals while accelerating the transition to the low-carbon system that science clearly shows is needed? The evolving energy and climate strategy in California presents an ideal case-study; in how to link different policy elements, as well as how the energy infrastructure of generation assets, transmission and distribution systems, and emerging technologies such as energy storage can make this a reality. A number of groups have produced realist models of parts of the energy system (see NREL’s Regional Energy Deployment System Model) and in working with a set of models, some quite clear opportunities emerge.

The interconnected elements of California’s energy and climate policy framework provide an important place to begin evaluating what can be, and what else is needed, to place an economy on a viable clean energy path. Today California has in place a suite of interdependent climate and energy regulations, beginning with AB32, the California Global Warming Solutions Act of 2006. From California’s commitment to return emissions levels to their 1990 ‘baseline’ by 2020, I propose three recommendations and focal areas in order to meet the state’s important energy and climate targets. 

Recommendation 1:
To continue and expand the ability to build a climate-friendly, job-creating economy, interim emissions reduction targets in 2030 and 2040 are vital to streamline and focus efforts on feeding the research, development, and deployment (RD&D) pipeline.

To enable accelerated learning and innovation (and profitable investment) around the interacting suite of climate, water, energy, job-creation and ecological innovations, my laboratory has built a series of electricity grid capacity expansion models called SWITCH (Solar, Wind, Integrated with Transmission and Conventional sources). These models are in use today in California, across the WECC, in Chile and China, and under development for India, East Africa, and Mexico. In the light of this recommendation, my analysis of the California and Western Electricity Coordinating Council (WECC) energy system using the SWITCH model very clearly indicates that an aggressive 2030 and 2040 RPS combined with a specific carbon reduction target are both vital to providing the state with the capacity to control costs and maximize job creation in the energy, water and land use/management sectors.

Specifically, this analysis shows that California and the west can cost effectively define a linear or ideally faster decarbonization path from 2020 to 2050 with milestones in 2030 and 2040.  My research group is currently exploring scenarios where we reduce emissions more than by 80% from the 1990 baseline.  This is likely to be needed.  Thus, a target in 2030 of 33% below 1990 levels, and 66% below the 1990 levels in 2040 would be prudent.  Later reductions may prove more difficult, so early action is vital.

An evaluation of ‘what if’ scenarios, using the SWITCH model, including changes from expected ‘business as usual’ prices and costs of different energy resources. 

Coordinated targets such as the Million Solar Roofs and Million Electric Vehicles targets mutually reinforce each other, and drive the sort of job creation that will make California more and more competitive globally as these standards diffuse around the world.  The dramatic increase in manufacturing in California as evidenced by Tesla Motors vehicle, and other EV startups, highlights the benefits that come from this systems-level approach to challenging targets for energy efficiency and clean energy commercial deployment opportunities.  This policy provides a strong market-based avenue to advancing goals for integrating storage into the California (and regional) energy mix in a way that makes excellent use of commercial trends and opportunities.

The grid storage mandate for California is a perfect example of this process.  The state should consider a series of system-level targets, such as those that incentivize both mobile (electric vehicle) and stationary storage capacity, and should identify opportunities for community and regional mini-grids that enhance supply reliability, cost certainty, and interact usefully with the IOU and municipal utilities across the state.

We find that California could meet its 2050 climate goals two decades earlier, in 2030, through a number of different technology-facilitated pathways.  For each the cost is negligibly different from the Business as Usual cost forecasts. Although difficult to achieve, the key is coordination between investments in energy efficiency, energy generation, and the construction of the transmission and distribution networks needed to enable these systems (Nelson, et al., 2012; Wei, et al., 2013; Mileva, et al., 2013). Specifically, coordination means that efforts to fund energy efficiency programs, new generation, and transmission needs to be managed in an interconnected way, otherwise the co-benefits can be lost. As a simple example, large scale desert-based solar or wind projects without the transmission the transmission capacity to bring them to market will not advance the goal of a reliable, low-cost path to decarbonization. By the same token, an effort to build out distributed urban and suburban solar generation incommensurate with the utilities’ need to recover costs and investments in distribution systems will not benefit the state.

Recommendation 2:
California should expand the number and scope of state-to-state and international partnerships around climate solutions. While AB32 and its associated laws and sectoral policies are an excellent basis for action, forming partnerships with neighboring states and the federal U.S. government, as well as with interested national and sub-national groups worldwide, will further advance our overall climate situation.

This focus on climate leadership is not just a high-concept platitude. This is a critical observation.  In my role as the Energy and Climate Fellowworking for the U.S. Secretary of State, I can document that the California Global Warming Solutions Act is demonstrably inspiring communities, states and nations worldwide to innovate and act.  This focus on an evolving AB32 process has brought investment in, and business opportunities to, California-based companies.

California’s interim targets under AB32 are vital to enabling and ensuring continuing use-inspired innovation that focuses talent on clear but challenging objectives.  The climate imperative is getting more and more immediate and costly – a consequence of fires, droughts, crop failures, and other extreme weather events as detailed by the American Meteorological Society and the Intergovernmental Panel on Climate Change (IPCC). The clear message from these data is that we must maintain or accelerate our momentum to meet the state’s climate targets.  The open letter to Governor Brown that I helped to author, and am proud to have signed with the Union of Concerned Scientists and a remarkable group of colleagues, highlights the increasingly dire climate data, and the vital and beneficial role that California’s proactive approach has taken to generating and profiting by solutions that AB32 had driven.

Recommendation 3:
Citizen, community, and business engagement—indeed, excitement over the steps and objectives—is vital to the sustainable energy and sustainable society process.

We must focus on the means to make behavior change profitable and easy and to build new partnerships that clarify and expand the benefits of a low-carbon economy to socioeconomically disadvantaged communities and individuals, by making the business case for a sustainable economy clear to the private sector both in and out of California.

Snapshot of the homepage of the Cool California City Challenge website.

A particularly important aspect of visualizing not only ones own carbon footprint but also the average over a local area, in this case by zip-code, (Jones and Kammen, 2014) is that this information empowers individuals to act. In fact the ‘take action’ pages on the website have been a huge source of excitement and conversation among users looking for means to reduce both their carbon footprint and household expenditures.  The interactive maps we generated have been accessed 100,00 online views/day, and have facilitated conversations about the embedded carbon in the good, services, and food we consume.  California must develop a plan to account for these embedded emissions in AB32.

Immediate conclusions from this work are 1) economy-wide carbon and resource accounting is an important first step, 2) this expanded accounting framework may lead to identifying important co-benefits not originally envisioned, and 3) without this detailed focus on individuals, the opportunities to build inclusive environmental and energy justice issues into the system may be lost. On the third point, a number of important innovations, such as making solar energy benefits and subsidies available to renters and other non-property owners, is an important social and economic goal that can be missed if we do not gather information on how policies impact all Californians.

In a recent project supported by the California Air Resources Board, we have found that climate protection can lead to immediate economic and quality of life improvements.  In the Cool California Challenge, we have found that residential cost savings, improved air quality are only two of the immediate benefits that can come from paying attention to and management of your carbon footprint.

Interactive calculator and map of carbon footprint of U. S. urban areas at the zip-code level, available at:


1. Jones, C. M. and Kammen, D. M. (2011) “Quantifying lower-carbon lifestyle opportunities for U.S. households and communities”, Environmental Science and Technology, 45, 4088–4095.

2. Jones, C. M. and Kammen, D. M. (2014) “Spatial distribution of U.S. carbon footprints reveals suburbanization offsets benefits of population density”, Environmental Science and Technology48 (2), 895 – 902.

3. Mileva, A., Nelson, J. H., Johnston, J., and Kammen, D. M. (2013) “SunShot Solar Power Reduces Costs and Uncertainty in Future Low-Carbon Electricity Systems,” Environmental Science & Technology, 47 (16), 9053 – 9060.

4. Nelson, J. H., Johnston, J., Mileva, A., Fripp, M., Hoffman, I., Petros-Good, A., Blanco, C., and Kammen, D. M. (2012) “High-resolution modeling of the western North American power system demonstrates low-cost and low-carbon futures”, Energy Policy, 43, 436–447.

5. Wei, M., Patadia, S. and Kammen, D. M. (2010) “Putting renewables and energy efficiency to work: How many jobs can the clean energy industry generate in the U. S.?” Energy Policy, 38, 919-931.  Online calculator:

6. Wei, M., Nelson, J. H., Greenblatt, J. B., Mileva, A., Johnston, J., Ting, M., Yang, C., Jones, C., McMahon, J. E. and Kammen, D. M. (2013) “Deep carbon reductions in California require electrification and integration across economic sectors”, Environmental Research Letters, 8.

Dr. Daniel M. Kammen is the Class of 1935 Distinguished Professor of Energy at the University of California, Berkeley, with parallel appointments in the Energy and Resources Group, the Goldman School of Public Policy, and the department of Nuclear Engineering. Amongst other roles, Dr. Kammen has been coordinating lead author on the Intergovernmental Panel on Climate Change (IPCC) – which was awarded with a Nobel Peace Prize in 2007 – since 1999 and continues his research in clean and sustainable energy infrastructure as the founding director of Renewable and Appropriate Energy Laboratory (RAEL).

Cover image "The Night Lights of the United States (as seen from space)" by NASA/GSFC is licensed under CC BY 2.0.