The old management aphorism "that which gets measured, gets managed" is all too true, but so is the old farmer's saying "a pig never got fattened by weighing it." In other words, yes, you should be collecting buckets of data, but that's the means to an end - acting on it is what counts.
Here's three things to do with your data:
1. Monitor progress
Choose metrics, set targets, monitor progress, act where necessary. Most data driven management works on this very simple loop. But care is needed to make sure that hitting short term targets doesn't distract from aiming for long term objectives - a good reason to eschew year on year targets (eg we will reduce carbon by 2% every year) in favour of stretch targets (we will be zero carbon by 2020).
2. Diagnose problems and find solutions
This is the fun bit for green geeks - you get to play detective. Analyse your data against time, against production output, against any other relevant variable. Compare sites, processes, teams and technologies. Do a material/energy/water balance to match inputs and outputs. Identify the big energy/water/material users for special attention.
Stuff will jump out at you - why is water use so high when the factory is shut down over Christmas? (answer: probably a leak), why does one site use more energy per unit output than another (potential answers: technology, control systems, staff culture). Why does one sales team have higher mileage per unit sold than another (potential answers: local ways of working, abuse/'jollies', different spread of customers).
3. Communicate and engage
Feedback to staff and external stakeholders needs information. But you have to choose your communication method to suit your audience. Engineers and accountants like graphs, pie charts and hard data. Creative types and the general public generally prefer more interpretative ways of expressing numbers - like the almost-ubiquitous infographic (check out this one from Fast Company on the impacts of climate change).
But here you must tread carefully or you'll end up in the greenwash mire. Make sure the data you use is accurate, up to date, relevant, representative and not misleading in anyway. Get an independent third party to check it and even endorse it for you.
Don't forget that numbers only provide part of the story. They can tell you about quantities, but are not so good at expressing qualities. A lot of important stuff (eg staff culture) doesn't get managed well because it can't be measured effectively. So don't just sit in front of your spreadsheets - get out there, walk about, talk to people and make sure what you witness and what you measure match up.