2025-10-27 – Weekly Environmental Engineer News : Embodied carbon in solar projects

Last week’s discussions focused on practical tools and methodologies for environmental engineers. Members shared experiences with handheld devices for testing dissolved oxygen and turbidity levels, essential for compliance with environmental regulations. There was also a robust conversation about the challenges of securing permits and community support for environmental projects. Additionally, the forum explored innovative approaches to reducing the carbon footprint of solar energy projects, highlighting the growing importance of sustainable practices in engineering.


This Week’s Hot Topics

Reliable handheld DO meters for NPDES grab samples
This thread dives into the reliability of various handheld dissolved oxygen meters, crucial for accurate environmental sampling and compliance.
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Reliable turbidity meters for stormwater outfalls
Members discuss the best turbidity meters for monitoring stormwater, an essential task for preventing environmental pollution.
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Permits, funding, and community buy-in
A practical discussion on navigating the complexities of obtaining permits and securing community support for environmental projects.
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Embodied carbon workflow for solar projects
This conversation highlights strategies for minimizing the carbon impact of solar projects, a key focus for sustainable engineering.
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FAQ/Guidelines
A useful resource for understanding forum rules and getting the most out of the community.
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Admin Guide: Getting Started
Essential reading for new members to navigate the forum efficiently and make the most of its resources.
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What Inspired You to Become an Environmental Engineer?
Members share personal stories that led them to pursue a career in environmental engineering.
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First Steps Into Environmental Engineering
An overview of how to begin a career in this field, with tips from experienced professionals.
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Key Skills Every Environmental Engineer Needs
A valuable discussion on the essential skills required to succeed in environmental engineering.
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Famous Environmental Engineering Feats
Explore some of the most impressive achievements in environmental engineering history.
Read more here


Wishing you a productive week ahead. Keep sharing your experiences and insights—it’s how we all grow.

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On our last solar build, we sped up permitting by adding a one-page embodied‑carbon summary to the packet; I used the free EC3 tool (EC3) to compare racking and foundation options and then asked vendors for mill‑specific EPDs since catalog numbers can be way off. If you’re already carrying “handheld DO/turbidity” kits for site checks, bring that EC sheet to community meetings — it answers the steel vs. concrete question fast.

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Nice add, @fchen_1 — we’ve been putting a single line in RFPs: “≤ X kgCO2e/kWdc for racking + foundations, EPDs required,” which nudged vendors toward screw piles and slag mixes without a fight. Small caveat: in remote markets we allow supplier-average EPDs upfront and lock the final number at submittals, or you’ll chase paperwork longer than you drive piles.

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One fast win for us was counting access roads, fencing, and laydown pads in the embodied‑carbon tally; switching to recycled asphalt millings for roads and timber posts shaved about 6–8 tCO2e per MW on a 40 MW site. We logged the reductions with EPDs via openEPD (https://openepd.buildingtransparency.org), but fencing EPDs are spotty, so we used conservative defaults — unglamorous work, big footprint.

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We funded a short CPT + test-pile program and used the data to trim average pile length by about 0.3 m without changing safety factors; it cut kgCO2e and steel costs, but you have to slot it in before racking procurement, @l_graham34.

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Procurement tweak that moved the needle for us: we added ‘bulk-pack on returnable pallets; no individual crates’ and required carriers to report km and backhauls; on an 80-MWdc site it cut packaging waste and truck runs. Bonus: tighter laydown meant less disturbed area, which made turbidity BMPs easier during a wet week. Caveat and resource: denser packs can bump breakage if handling isn’t dialed, and EPEAT’s PV registry is handy for quick vendor screening https://www.epeat.net/photovoltaic-modules-inverters-storage.

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On our stormwater comms, we baked a “pivot trigger” into the 90-day plan — if NOAA posts a flood advisory (https://alerts.weather.gov), we bump the queue and ship a 150-word explainer within two hours from a pre-approved Airtable template… It’s great for “rapidly changing news cycles,” but only works if legal and ops refresh the template every Friday or the facts get stale.

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Quick win from our last 100‑MWdc job: we required EPDs for racking and used EC3 for concrete, swapping inverter pad mixes to 50% slag and trimming racking gauge where wind allowed, which cut BOS embodied carbon about 8–10% with no performance hit (EC3). Small caveat: slag lead times stretched the pour by a week in winter — @claireb_87, have you tried geopolymers or just stuck with SCMs?

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