Women in Power: Linda Maepa

Feb-FeatureMaepaMy name is Linda Maepa and I’m the child of an electrical engineer who came to the US from South Africa and a medical technologist who arrived from Swaziland, both in the late 1960s. I am a scientist, organic farmer, inventor, mother and entrepreneur. I am also an engineer.

In late 2006, I was faced with a choice: build a team to achieve rapid human genome sequencing, ushering in a new era of personalized medicine, or help create affordable, resilient energy storage, transforming transportation, critical infrastructure and global markets. Choosing energy storage was about the hunt, the thrill of inventing new technologies, and about triage, the need to first secure our energy future so we could make use of personalized medicines’ benefits for a long time. I go out of my way, not necessarily to find and take on the big problems, but to uncover and deploy the big solutions.

Engineering as entrepreneurship

I have started two energy storage companies: ElectronVault (Silicon Valley, Region 6; I am the Chief Operating Officer) and ElectronVault Energy Systems (Johannesburg, Region 8; I serve as CEO). The US company addresses electric vehicles and distributed generation while the South African organization focuses on infrastructure energy storage: solar, wind, hydro, remote and commercial/industrial power. We have hardware deployed in Africa, Asia, Europe and the US. Years of research and development have provided me with two big insights into what I call the Shiny Technology vs Solving a Problem conundrum:

First, the heart of large-format battery system design is the engineering of complex systems. System safety, performance, reliability, manufacturing yield, and cost are key emergent properties of a battery system design. Complex system engineering is inherently shiny and exciting.

Second, creating the best battery system is necessary but not sufficient to address global energy and transportation needs. Instead, what is needed is to create worked solutions. Ultimately, it is pairing shiny technology with real world solutions that makes that technology compelling.

Adding nanotech to electric vehicle battery connections is the definition of shiny

Although ElectronVault addresses a wide spectrum of energy storage technologies from electrochemical such
as batteries and fuel cells to electrostatic such as capacitors and mechanical such as compressed air and pumped hydro, our initial focus began with Lithium ion batteries. My partner and co-founder, Rob Ferber, is an electrochemist who converted the AC Propulsion TZero to Lithium ion batteries in 2002. This was the prototype that launched Tesla Motors and became their first vehicle, the Tesla Roadster. His detailed survey of the electric vehicle battery space and where the technology needed to be in order for mass adoption of electric vehicles to become a reality was our starting point.


High performance battery system design relies upon high quality, stable and low resistance connections to battery cells and preservation of usable cell lifespan.

Battery systems age, and suffer performance losses, as battery cells increase in internal resistance over time. A battery system has multiple additional sources of resistance, such as its passive currentcarrying components, one of which is caused by resistive losses due to the quality of the connection to the positive and negative terminal of each cell. Therefore, the internal resistance of a battery system is a measure of both the aggregate internal resistance of the cells in the system plus the resistance of the passive current-carrying components of the battery system.

The quality of cell terminal connections for cell to cell interconnection has a significant impact on the reliability of battery system performance over the design life of the battery system as well as the usable lifespan of the component battery cells. With high quality connections, the overall battery system internal resistance is kept low over time. These low resistance connections, also produce less heat at a cell’s terminal ends. After all, waste heat must obey P=I^2R. Because the connection points do not become hotspots, premature increase in cell internal resistance can be avoided, which translates to longer usable cell lifespan. That is, even though the battery cells naturally increase in internal resistance over time, that rate of increase can be significantly slowed relative to higher resistance (hot spot producing) interconnection technologies such as welding, bolting, and soldering.


The invention of a nanomaterial that enables high quality electrical connections to battery cells remains one of my fondest memories of the winter of 2008-2009.

Dispatchable renewable energy solves a problem

But this early technology development only solves the challenges that a battery system manufacturer encounters. What’s important is figuring out what technology development can do for someone else, like a solar photovoltaic farm. When it comes to renewable integration, it is generally understood that solar power is only available during the day and that wind power is only available when the wind is blowing. Adding a battery system will overcome these deficiencies in power generation vs time.

But what if the problem to be solved isn’t that of inconvenient generation time? What if the problem is one of reliable capacity (baseload power generation), dispatchability (predictable market participation) and revenue generation (project finance and viability)?

My colleagues and I spend a lot of time analyzing the dream of affordable energy storage to discover the right questions to ask so we can develop the energy storage solutions for the problems uncovered by those questions.

SunVault is the name of the solar photovoltaic energy storage solution we invented: dispatchable solar PV that increases project IRR and provides reliable power around the clock.

I try to bring all that I am to my work

Prior to ElectronVault, I had started other companies in areas as varied as internet publishing and fashion design. My professional experience builds on a lifelong love affair with computing and includes information technology, cybersecurity and business consulting in high tech manufacturing, insurance and state government. It is delightful yet distressing to me that I am able to bring my cybersecurity expertise to the utility industry, specifically as it relates to secure-by-design battery systems. In academia, I managed a genomics lab, conducted seismological and botanical field work as well as work in paleomagnetics. All of this experience continues to inform what I do today in energy storage and effective applications of storage to the grid.

I balance the passion I put into my work by putting passion into serving myself and others such as reading, traveling, learning languages, serving on boards, raising my three children and helping run our family’s organic farm and seed conservation business.

Growing Up IEEE

Like me, my children are growing up with IEEE Spectrum as casual home reading material. Some of my earliest memories are of the substation my father worked at after graduating as an EE from Purdue University, the Lego blocks he brought home after a trip to Europe in the mid-1970s after joining Black & Veatch, and my introduction to solar power and computer programming in the late 1970s. When I was in elementary school, we moved to Saudi Arabia so my father could help build Eastern Province electrical infrastructure for the Kingdom. My world expanded during the early 1980s as we did not live in an isolated compound but amongst the general populace of Al Khobar. I loved learning a new culture, a new language, and studying at the International School. The lessons were multiplied as we spent considerable time each summer traveling through the Philippines, Thailand, China, Japan, Hong Kong, India, Egypt, Jordan, Kenya, Swaziland, and the
then-new country of Zimbabwe. It seemed we knew so many of my father’s colleagues in these far-flung places. In hindsight, the common thread is engineering around the world, rural electrification, commercial/industrial physical plants, and distribution networks. In the moment, the world and the people living in it became familiar. The outcome, in this modern day where emerging market growth
(and hence, electrical infrastructure growth) is booming, is that their problems are immediately understandable and important to me.


I still speak a little Arabic. The first words I learned were ‘ahlan wa sahlan ( أهلاً بك ): Welcome.

Learning and gaining confidence in the midst of struggle

My Bachelor of Science degree is in Geobiology from the California Institute of Technology, also known as Caltech. My research focused on protein co-evolution with the Earth’s early atmosphere and was the first geobiology degree granted since my mentor and research advisor, Dr. Joseph Kirschvink, received his in the mid-1970s. 1989, the year I entered Caltech, is notable in the history of the Institute as being the first year with almost 1/3 women in the incoming Freshman class. I believe the large number of women entering alongside me was critical to my success at the school and to my career. Caltech is notoriously academically challenging. Had there been fewer women, it would have been easy for myself and others to say that my struggles were due to my gender and to personal inadequacy. However, because there were a large number of fellow women students, it was obvious that my struggles were normal for any Caltech student, and just like others before me, I overcame them. Instead of worrying about whether I belonged at the university, I was able to gain an understanding that my unconventional approach to problem solving was valid and that even my mistakes could be interesting. This confidence and freedom to experiment are important tools I bring to my work today.

In support of women in science and engineering, it is my privilege to be one of the founders of the Caltech Women’s Center which opened in 1993.

IEEE PES Women in Power

My recent support of women in science and engineering focuses on leadership development through working groups, participation in advisory boards and mentoring other women. So I was excited to discover that the IEEE PES Women in Power community had been created. Today is one of the most exciting times in the history of the power and energy industry. Emerging market growth spurs new electrical infrastructure needs on a global basis, existing infrastructure requires recapitalization with new technologies and asset classes entering into the mix, while changing regulatory and economic requirements are shaping what, where, who, and how projects are planned, implemented, financed, and operated. In order to build the necessary engineering solutions, the expertise, creativity and perspective of all who qualify is needed.

Women in Power exists as a global leadership resource for our industry. It brings together women leaders in power and energy and connects them with leadership development resources and networking across industry, academia and government. Identifying women who are willing to serve in governance, executive, tenured, and government-appointed positions, on organizing committees, and as conference speakers and media sources is easier because of the vision that enables IEEE PES Women in Power to exist.

I am honored to serve as the organization’s inaugural Director of Education and Outreach, providing strategic and operational support for the educational, outreach, marketing and public relations efforts of IEEE PES Women in Power. Guided by the organizational Mission, my colleagues and I aim to provide a world-class platform for convening male and female leaders in power and energy in order to promote more diversity in our industry’s leadership. My goal as Director of Education and Outreach is for IEEE PES Women in Power to become the leading global resource for women leaders and educators to the wider power and energy industry, media and policymakers.

I encourage new members and partners to join and collaborate with Women in Power. For more information about the organization, please visit http://pes-women-in-power.org.

Lessons learned

I hope that by sharing my own story, I can inspire others to make use of their own non-traditional
experience to create impactful solutions in the power and energy industry. The difference between
engineering and science is the goal to solve a problem of the world today. So whenever new
technology is put on the table, always remember the root problem to be solved.