AI for solar and storage engineering

Higher Returns.
Faster Decisions.

Find the highest-IRR design for every site, assess the risks before you commit capital, and forecast long-term yield from P50 to P99. Delivered at the speed of software and the rigour of an independent engineer.

50+ GW

solar and storage engineered and assessed

30+ countries

in established and emerging markets

Days, not weeks

from site data to bankable results

Trusted by

  • DNV logo
  • Wind Pioneers logo
  • Energy Abundance logo
  • Carbon Resilience logo
  • Naseby logo
  • BBCO-Energy logo
  • Megawatts logo
  • YDE logo

Find the best design before detailed engineering starts

AI runs every option. Our solar and storage engineers make the call. You commit capital to the best design, not the first one.

Highest IRR
200+designs per site

Every design ranked by return

Layouts, equipment and grid limits, all fully simulated and ranked by IRR.

Traditional engineeringWeeksTomsawyerSame day
< 24 hrfull re-run

Updated when inputs change

New tariff, module price or grid limit? The full analysis re-runs the same day, so your numbers stay current through the deal.

GW-scaleportfolios, screened in weeks

Every site screened, not sampled

Site-by-site layout and yield across whole portfolios. Know where development capital belongs before you spend it.

P99P50
P50 to P99yield forecasts

Numbers your lender can verify

Every assumption cites its source and date. Reviewers check your model instead of rebuilding it.

Data library

Every number your analysis needs, already in place

What the plant costs and produces, and what its energy is worth. Both sides of the business case are covered from day one, so your project starts with analysis instead of data collection.

Supply side

What it costs and what it produces

  • Modules

    Every current Tier-1 datasheet and power bin, across TOPCon, HJT, back-contact, PERC and thin film

  • Inverters

    String, central, MV skids and micro-inverters

  • Capex and opex

    Equipment, balance of system, installation and O&M prices for every major region

  • Weather and terrain

    Irradiance, temperature, terrain and horizon for any site, or your own Solargis and PVsyst files

Your decision

IRRNPVLCOEPayback

Demand side

What the energy is worth

  • Wholesale prices

    Day-ahead prices, solar capture rates and negative-price hours

  • PPA and retail tariffs

    PPA indices, C&I retail prices, import and export tariffs, net metering

  • Load profiles

    Commercial and industrial demand shapes, or your own 8760-hour meter data

  • Grid limits and curtailment

    Export caps and curtailment history, so storage is sized to what the grid takes

Every value carries its source and date

Your BoQ, PAN files and tariffs replace any default

Growing market coverage

How we get you there

The highest-IRR design exists for every site. We find it early, before the design is locked and costly to change.

01

Send us what you have

A KMZ, a PVsyst file, a data room. AI agents extract the inputs. No templates to fill.

02

Every option simulated, not estimated

Layouts, equipment, BESS sizes, DC/AC ratios, each run through hourly energy and cash-flow models. No shortcut estimate decides the ranking.

03

An engineer reviews it

Our engineers apply the judgement a model can't: loss factors, uncertainty and the questions your lender will ask.

04

You brief your EPC with a target

A recommended design with full financials. Your EPC builds to a known optimum, not their first pass.

Your brief: maximise IRR, at least 2.0 MWp, capex under $1.10M

Illustrative
Screening modules, inverters and mounting0 designs simulated
12%14%16%$0.8M$0.9M$1.0M$1.1M$1.2M$1.3MCapex →Project IRR ↑Capex limit $1.10MABOver budget 16.2%Recommended 15.6%
OptionMWpCapexIRRBrief
Design A2.00$1.04M15.0%Meets
Design B2.16$1.13M14.6%Over capex
Recommended2.06$1.05M15.6%Meets

A and B are typical feasibility-stage designs. Full search found a higher-IRR option within the same constraints.

What you receive

Everything your board, lender or EPC needs to act on the result, and no new software for your team to run.

A clear answer

The recommended design or finding, with the alternatives we ruled out and why.

Bankable numbers

P50 to P99 yield, IRR, LCOE and capex, each traceable to its source.

Files your team can use

A report, an Excel model, and layouts for CAD and Google Earth.

Updates when things change

Re-runs when prices, tariffs or grid limits move. For regular work, a tool we build and maintain for your team.

Engineering services

Your engineering team, extended

Take on more sites without adding headcount. From resource data and layout design to energy yield, battery storage, due diligence and operating plant reviews, we cover the full project lifecycle. AI handles the heavy analysis, and our engineers own the results.

Simulation-ready timeseries

Generation timeseries built on real weather history, ready for your PPA, hybrid and dispatch models.

  • Irradiance checked across several sources, with temperature profiles
  • 20+ years of historical data, not only a typical year
  • Generation specific to the location, equipment and design
  • Hourly or sub-hourly, in the format your models already read

Deliverables: CSV/Excel timeseries, source comparison

System configuration optimisation

Every equipment and configuration mix compared on energy and cost, to find the design with the highest IRR.

  • Tracker vs fixed-tilt, rooftop and carport options
  • Tilt, GCR, module, inverter and DC/AC ratio searched together
  • Each option fully simulated, with line-item capex and IRR
  • Your current design or EPC proposal as the baseline, so the gain is clear

Deliverables: configuration matrix, IRR ranking, comparison with your baseline

Layout design

Site-adapted layouts for ground-mount and rooftop solar, ready for planning and EPC tender.

  • Strings, inverters, MV stations and cable routing designed together and checked by an engineer
  • BESS and inverter siting
  • Land-use and terrain constraints from SRTM, satellite imagery and stakeholder input
  • CAD and PDF layouts for planning and approvals

Deliverables: DXF and PDF layout, 3-D KMZ, block plan, bill of quantities

Energy yield assessment

Bankable P50 to P99 energy yield in PVsyst, with every loss factor documented.

  • P50, P90 and P99 from 20+ years of weather data, plus TMY runs
  • Soiling, electrical and shading losses, including complex urban sites
  • Side-by-side yield comparison across designs
  • PVsyst files your team or the lender's engineer can re-run

Deliverables: yield report with loss breakdown, PVsyst project files, P50/P90/P99 table

Solar energy yield assessment showing monthly generation, P50 P90 uncertainty distribution, and satellite site view

Battery storage assessment

Battery size and dispatch modelled together with the PV design, tariff and grid limit, so you prove the business case before you commit.

  • Solar-BESS pairing, including curtailment recovery under export limits
  • Power and energy sized separately, with cost-benefit for each option
  • DC-coupled storage and dispatch modelling
  • Behind-the-meter storage for peak shaving, demand charges, EV charging and backup

Deliverables: sizing study, dispatch model, business case

Grid-connected solar PV and battery energy storage system diagram with BESS dispatch charts

Technical due diligence and lender's advisory

Independent review from pre-construction bankability to operational hindcasting.

  • Pre-construction and financing: design basis, resource assumptions, equipment and construction readiness
  • Bankability reports, risk registers and CP support to financial close
  • Acquisition and operations: pre-acquisition review of design, contracts, permits and technology risk
  • Hindcasting, yield reconciliation and revised production estimates

Deliverables: IE-style report, risk register, revised P50

200 MW solar + 80 MWh BESS

Pre-construction · lender's technical advisory

Financing
Resource basis

Multi-source validated, within 2% of independent estimate

Design basis

Configuration confirmed optimal for site conditions

Equipment

Inverter firmware update required for grid code

Bankability

Risk register complete, CP inputs delivered to lender

Construction

Grid approval pending, 8-week delay risk

350 MW portfolio (3 sites)

Acquisition review · operational + pre-construction

M&A
Energy yield

P50 overstated by 3.1% at Site B; revised estimate provided

Contracts

PPA terms and EPC scope consistent with design

Operational review

Hindcast shows 4.2% underperformance at Site A; soiling suspected

Technology risk

Module and BESS technology reviewed, no red flags

Operating plant review and long-term energy forecasts

An accurate view of what an operating plant will produce over its remaining life, for acquisitions, refinancing and asset management.

  • Monthly reconciliation of irradiance, energy, PR and availability against expected values
  • Root cause analysis of underperformance: soiling, degradation, availability and curtailment
  • Satellite-bias correction and yield re-modelling from operational data
  • P50 to P99 forecasts over one-year and ten-year periods for the remaining asset life

Deliverables: performance review report, remaining-life P50/P90 forecast, Excel model

Remaining-life forecast · 100 MWp operating plant

YearPRP50 GWhP90 GWhP99 GWh
202778.9%158.2151.4145.0
203276.4%153.1146.6140.3
203774.0%148.3141.9135.9
204271.6%143.5137.3131.5
204769.3%138.9133.0127.3

Built from monthly operating data: measured irradiance, energy, PR and availability, reconciled against expected values before forecasting.

Built for everyone who decides on a solar or storage project

Developers

Know which sites are worth pursuing before you spend on detailed design. Find the highest-IRR configuration, with yield assessments that hold up at financing.

Pre-feasibility and go/no-go · Layout and configuration · Energy yield assessment · BESS sizing

Investors

Independent review of assets and portfolios before you acquire or commit capital.

Pre-acquisition due diligence · Multi-site portfolio review · Red-flag review · P50 to P99 yield estimates

Lenders

Independent technical review from financial close through operations.

Design and resource basis review · Risk registers · Conditions precedent support · Yield reconciliation

Asset owners

Find out where operating plants lose energy and what your portfolio will really produce over its life.

Operating plant review · Under-performance diagnosis · PR and availability analysis · Long-term energy forecasts

Advisory firms

Engineering capacity for your projects, delivered in your report format.

Subcontracted yield and DD · Simulation-ready timeseries · Portfolio-scale reviews · Retainer support

Project types

Utility-scale solarSolar + BESSStandalone BESSC&I and captive solar

Case studies

Proven results in solar and storage

Solar farm feasibility for an AI data centre hub, United States

Develop · Data centre · United States

5 GW

100% green energy feasibility for an AI data centre hub

Hourly solar production profiles across 5 GW, delivered in days instead of months.

Utility-scale solar portfolio, Queensland, Australia

Develop · Utility-scale · Australia

15.3 GWp in 3 weeks

Site-by-site pre-feasibility for a Queensland portfolio

Investors knew which projects to prioritise before committing further development spend.

Utility-scale solar acquisition, Southeast Asia

Acquire · 150+ MWp · Southeast Asia

~18% less capacity

Than the developer claimed, found before the investor committed

14 red flags registered, 5 rated high.

Commercial and industrial rooftop solar, Abu Dhabi

Develop · C&I rooftop · Abu Dhabi

+4% IRR

Found just before financial close

8% lower cost and 15 kWh/kWp more yield than the client's own design.

Solar and battery storage at a motorway services site, UK

Storage · Solar + BESS · UK

15 MW avoided

Of power conversion on a motorway services site

A 10 MW battery recovers as much curtailed solar as a 25 MW one, at the same 25 MWh.

EPC bid review for solar farms across Europe

Advisory · EPC bid review · Europe

Multi-site

EPC bidder's package review for solar farms across Europe

Independent technical comparison of competing EPC proposals for a leading global advisory firm.

PV and hybrid renewable site screening, Italy

Develop · Site screening · Italy

Hybrid solar

PV and hybrid renewable site screening and ranking

Early-stage feasibility assessment for a leading global advisory firm's Italian pipeline.

Utility-scale solar due diligence, Africa and Middle East

Advisory · DD · Africa and Middle East

>1 GWp

Automated due diligence for a global advisory firm

Batch yield re-modelling and design audits, delivered as P50/P90 forecasts.

Working on a similar project?

Tell us the site and the question. We'll figure out the analysis on a 30-minute call.

Team

Engineering that gets projects financed

We've done independent engineering the traditional way. Now we build the AI that does it in days.

Bishal Madhab, founder of Tomsawyer

Bishal Madhab

Founder

Bishal started in energy systems research at Carnegie Mellon University, modelling solar and wind power variability, and took that work into applied research at a leading energy policy think tank advising the Indian government, within international consortia including the US-India SERIIUS programme with NREL. His research is published in peer-reviewed journals including Solar Energy.

He went on to co-found a machine learning company forecasting renewable power generation, deployed across 2.5 GW. As Battery Storage Lead at DNV, he helped establish the battery storage advisory practice across Asia Pacific, focused on co-located solar and storage. He then joined Wind Pioneers as its first engineer and helped build the firm's global consulting practice, now active in 40+ international markets.

He founded Tomsawyer in 2019 and built its simulation engine from the ground up. Since then, the team has delivered engineering on more than 50 GW of solar and storage projects.

The team

AI engineers, software engineers and energy engineers with significant experience working with Bishal across multiple GW of solar, wind and storage projects worldwide.

IndiaSingaporeUnited States

Testimonials

What our clients say

"Tomsawyer performed the work competently and met our expectations throughout the project. They showed a diligent approach and attention to details, and worked in a professional manner, ensuring that the tasks were completed on time and to the required standards. We were satisfied with the quality of their work and appreciate the support they provided."

DNV AS logo

Ignacio Becares

Principal Consultant, DNV AS

"It was a pleasure to collaborate with you, and I really appreciated the fact that you understood our sense of urgency and managed to adapt to our short timelines. The pre-feasibility study documentation was according to our expectations, and you even went beyond with helping us selecting some initial equipment to provide energy estimations."

Carbon Resilience logo

William Gaillard

Former Wind Head, Carbon Resilience

"The Tomsawyer team was instrumental in supporting the technical layout design for our first utility-scale solar development in the UK, up to securing planning consent. Their sound knowledge of solar optimization enabled the production of an efficient layout, integrating DC-coupled BESS."

Naseby Energy Holdings logo

Ashley Vandermeer

COO, Naseby Energy Holdings

"Tomsawyer helped us clearly understand the long-term techno-economics of distributed energy asset and sensitivities with respect to configuration changes. They were very collaborative and provided efficient and highly professional support."

Megawatts logo

Andrew Koh

Managing Director, Megawatts

"What I would say about Tomsawyer is that you are very professional, very dedicated to the work delivering to BBCO Energy. Tomsawyer delivered its advisory service in timely manner, with high responsibility, and caring about customer's problems. I do believe, Tomsawyer will add very good value to its partners/customers by delivering their high quality of work."

BBCO Energy Vietnam logo

Khanh-Loc Nguyen

CEO, BBCO Energy Vietnam

Engineering since 2019.
AI-native today.

Our automated simulation stack has delivered independent engineering for solar and storage projects worldwide. We've now rebuilt it around AI, so the same engineering standard arrives in days, not weeks.

World map of countries where Tomsawyer has delivered engineering

Countries where we've delivered engineering

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