Erick C. Jones Jr.

Projects · Food, Energy and Water Systems

Food, Energy and Water Systems

Planning electricity and water together, for homes and farms, so that local solar, rainwater and desalination pay off.

Two charts side by side. Left, labeled 'Community: 32 Austin homes, scaled up (2021)': annual electricity and water cost per home against community size, with a dashed line at $3,442 for buying everything from the utilities. The co-optimized electricity-and-water line falls from about $3,060 for homes acting alone to about $2,420 for 3,200 homes; water-only and electricity-only lines fall less; a capped-utility line starts at $3,776 and falls to about $2,544. Right, labeled 'Farm: a 200-hectare wheat farm (2022)': extra expected 25-year profit from advance knowledge. When all climates are thought equally likely, knowing which climate will arrive is worth about $98,000 and also knowing each year's weather adds about $10,000, for $109,000; when a dry climate is thought most likely, the figures are about $65,000 and $12,000, for $77,000.
Left: pooling investments across more homes, and planning electricity and water together, lowers the yearly cost per home. Right: for the farm, knowing in advance which climate will arrive is worth far more than knowing each year's weather.Panels rendered by the SEAR Lab from the papers' public code and results (sear-labs/water-energy-coopt-scs-2021 and sear-labs/fews-stochopt-esd-2022); Jones Jr. & Leibowicz (2021), Sustainable Cities and Society, and (2022), Environment Systems and Decisions

In plain English

What we grow, the energy it takes and the water it uses are one system. Pumping and treating water takes electricity, and farms need both to produce food. Households and farms now have their own options, such as rooftop solar, rainwater tanks, graywater recycling and small desalination units. But these are costly and long-lived, and they depend on sun, rain and a climate that nobody can predict. This line of work asks when such investments pay off, and how to plan them.

Dr. Jones developed it with Benjamin D. Leibowicz at the University of Texas at Austin, in two papers built on optimization models. The first, in Sustainable Cities and Society (2021), sized electricity and water technologies for a neighborhood of Austin homes and found that planning both together, and investing as a community, lowered costs. The second, in Environment Systems and Decisions (2022), moved to a farm deciding how much solar power and desalination to build before knowing whether the coming decades would be wet or dry. Both models are public, so others can rerun and adapt them.

Main points

  • Treats electricity and water as one planning problem instead of two separate utilities.
  • Moves from a neighborhood of homes to a single farm, showing the same modeling approach works at different scales.
  • Adds uncertainty: the farm model commits to investments before the climate is known, then tests them against thousands of simulated weather years.
  • Both code repositories are public with archived releases; the farm model reproduces its paper's tables, and the community model ships its scenario results with a synthetic input set in place of licensed household data.

Interactive demoFood, energy and water under climate risk →

Papers

Sharing home solar and water systems makes them pay off

Jones, E.C., Jr., & Leibowicz, B.D. (2021). Co-optimization and community: Maximizing the benefits of distributed electricity and water technologies. Sustainable Cities and Society, 64, 102515. https://doi.org/10.1016/j.scs.2020.102515

Can homes save by making their own power and water? Pooling investments across a neighborhood and planning both together cut costs and emissions.

  • Co-optimizing electricity and water gave the lowest cost at every community size: about $3,060 a year per home for homes acting alone and about $2,420 for a pooled community of 3,200 homes, against about $3,440 when buying everything from the utilities.
  • Water technologies such as rainwater harvesting and graywater recycling saved these homes more money than electricity technologies did on their own.
  • The benefit of planning both together grows with scale: only in the 3,200-home community did joint planning save more than the electricity-only and water-only savings added together.
  • Distributed water systems running on grid electricity always increased carbon emissions, because small systems use more energy than the city's water plants; co-optimized systems that pair them with local solar and wind always reduced emissions.

Correction note. The paper says planning for electricity alone gives higher local electricity shares than co-optimizing at every community size except homes acting alone; the published scenario tables show this is also not true at 3,200 homes (59.6% vs 60.3%).

Two-panel chart. Left: annual electricity and water cost per home against community size, with a dashed line at $3,442 for utilities only. The co-optimized line falls from about $3,056 for homes acting alone to about $2,418 for 3,200 homes; water-only and electricity-only lines fall less; the capped-utility line starts above the utility cost at $3,776 and falls to about $2,544. Right: in the co-optimized case, the share of electricity produced locally rises from 3% to about 60%, and the share of water from 22% to 47%, as community size grows from single homes to 3,200 homes.
Left: average annual cost of electricity and water per home as more homes pool their investments, for each planning approach, against buying everything from the utilities. Right: share of electricity and water produced by distributed technologies in the co-optimized case. Values are the paper's scenario results as published in its public code repository; no household-level data are shown.Rendered by the SEAR Lab from the paper's scenario aggregates in its public repository (sear-labs/water-energy-coopt-scs-2021)

For farm water and solar investments, the climate matters most

Jones, E.C., Jr., & Leibowicz, B.D. (2022). Climate risk management in agriculture using alternative electricity and water resources: A stochastic programming framework. Environment Systems and Decisions, 42(1), 117–135. https://doi.org/10.1007/s10669-021-09838-8

How should a farm invest in desalination and solar under an unknown climate? The climate that arrives shapes profit far more than yearly weather.

  • Expected 25-year profit depended heavily on the farm's beliefs: about $2.25 million when all four climates were treated as equally likely, and about $1.90 million when a dry climate was thought most likely.
  • With climates equally likely, knowing in advance which climate would arrive was worth about $98,000 of the $109,000 value of perfect information; also knowing each year's weather added only about $10,000.
  • Hedging across all climates gained almost nothing over simply planning for the average climate: $0.49 when climates were equally likely and $941 when a dry climate was most likely.
  • Preparing aggressively for an extreme climate can cause significant losses if a more moderate climate arrives instead.
Two-panel chart. Left: stacked bars for four climates showing the share of simulated years at five rainfall levels; the Dry climate is mostly dry years (20% very dry, 50% dry, 25% average), Dry-moderate is mostly average years (54%), Moderate is spread evenly at 20% per level, and Wet is mostly wet (45%) and very wet (30%) years. Right: the extra expected 25-year profit from advance knowledge. When all climates are equally likely, knowing the climate is worth about $98,000 and also knowing the weather adds about $10,000, for $109,000 in total; when a dry climate is thought most likely, the figures are about $65,000 and $12,000, for $77,000. Hedging instead of planning for the average climate is worth under $1 and about $1,000.
Left: the four climate futures the farm plans for, shown as the share of simulated years at each rainfall level. Right: how much expected profit over 25 years the farm would gain by knowing, before it invests, which climate will arrive and each year's weather, under each of the two beliefs about which climate is likely. Values computed by the paper's public code.Rendered by the SEAR Lab from the paper's public code, inputs and results (sear-labs/fews-stochopt-esd-2022)

People

  • Erick C. Jones Jr., PhD, PEPrincipal Investigator · SEAR Lab directorin
  • Benjamin D. LeibowiczAuthor, Sustainable Cities and Society 2021 · Author, Environment Systems and Decisions 2022

Profiles marked in link to LinkedIn. More past and present lab members are on the SEAR Lab team page.

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