Substitution of materials, equipment and low carbon fuels for high carbon fuels is underway and moving forward faster in some countries and economic sectors than others.  Substitution of manufactured equipment for fuels adds “life cycle carbon” to historical and on-going GHG emissions.  To what extent do GHGs emitted in creating low carbon energy economies retard overall decarbonization progress?  Life cycle carbon emissions for the years 2020 through 2029 add up to a minimum of 35 billion metric tons of CO2-eq, or roughly a year’s worth of current global energy related GHG emissions.  Overall life cycle carbon emissions will continue to increase after 2029 at least until direct global GHG emissions are brought under control. 

Just as the atmosphere’s capacity to absorb GHGs without affecting climate is limited, so is the earth’s capacity to supply materials to replace those that are used only once.   In a renewable energy context, there are two basic solutions.  First, there is no technical reason renewable energy equipment cannot be built to last decades longer than it otherwise might.  How can renewable energy markets and policies reward durability and long, low maintenance project and system operation even as major supply chain industries continue to thrive on planned obsolescence?  Second, renewable energy material and component recovery and reuse is feasible but not generally either mandatory or economically rewarding.  Will publicly financed renewable energy waste recovery be necessary, and which governments will take the lead in making it work fairly and efficiently?

The menu of energy related actions that can be identified and prioritized in local climate action plans can be displayed in two main categories. Electricity and gas fuel decarbonization elements are additive, synergistic, and comparably effective in most local cases. They support faster decarbonization progress than renewable electricity alone. They are inter-dependent to the extent energy resilience is best (most cost-effectively and completely) achieved by including gas fueled electricity supply in the local electricity supply mix. Each menu category requires local implementation capacity. Prioritization of the categories should give close consideration to implementation capacity and strategies and actions to upgrade it.

In a single decade electricity generation capacity additions have shifted to natural gas and renewables while solar generation capacity additions in California have been a mix of large and small projects that enabled faster overall expansion.

When IRESN took up the topic of “integrated renewable energy systems” a decade ago, we imagined an expanding renewable integration challenge driven by community-scale and building-scale renewable energy systems as well by utility-scale power plants.  Now new technologies are changing what we imagined into a real and urgent challenge.  The figure summarizes vectors of energy sector change that are already in effect.  Collaborative planning will need to be local as well as regional.