rmi green upgrade calculator case study

An in-depth web-based tool allowing energy professionals to analyse the economic and environmental impact of home and transport upgrades

After supporting RMI with various other small web-based projects, we received a brief for an online calculator tool, based on a large existing Microsoft Excel model. The model takes hundreds of inputs regarding your upgrade scenario, then conducts many complex calculations to produce a share-able output detailing many ways how the specific upgrades will affect many relevant metrics. Output metrics range from your annual costs year-on-year to how many millions of tonnes of carbon dioxide equivalent (MTCO2e) emissions you will save in your lifetime.

Convert a very complex and difficult to use Microsoft Excel model to an easy-to-use web-based tool. Allowing energy professionals to analyse millions of home and transportational green upgrade scenarios easily.

RMI is a US-headquartered business specialising in reducing carbon emissions, with a view to helping the world cut greenhouse gas emissions at least 50% by 2030. We have been one of RMIs digital partners for a number of years now, so to be given the opportunity to work on this project was a privilege, given its significance and lofty ambitions.

The RMI Green Upgrade calculator is a tool which allows the end-user to input a vast array of numbers and choices, which align to a particular scenario, these numbers and choices are then sent to a backend application, which processes the information and returns many pieces of information, which the frontend then presents back to the end-user in a series of tables, graphs and illustrations.

We were provided with a complex Microsoft Excel document which contained all logic and calculations, so the main task of this project was to convert that same logic into an API which could take all the same inputs, and produce the same outputs. Further to this, we integrated third-party APIs which factor in live information to the resultset (this functionality was not possible in the Excel document).

The first part of this project was to fully understand the Excel model. This was certainly no mean feat considering the complexity of the document and the subject matter! This involved multiple members of the team to get an overall clear picture of the calculations and the key parts of the logic.

Once we had a working knowledge of the calculations, we could split the team into 2 parts for frontend and backend implementation. This split made a lot of sense as it meant we could isolate the team easily with no cross-over, provide better redundancy and isolation of the moving parts, and also easily allow separate access to the backend later via a public API.

After some initial prototyping, we further split the frontend into separate projects for form input management (validation and integration) and visual design.

The backend has gone through many iterations to get it aligned correctly with the Excel model, and our robust testing methods have allowed us to constantly iterate on improvements and additions.

Since launching the Green Upgrade calculator in April 2024 many hundreds of energy professionals have been able to accurately analyse their green upgrade scenarios better than ever before. This will hopefully reduce friction in cutting greenhouse gas emissions.