There’s been a lot of talk recently about what sort of budget is required per house to make major CO2 savings. We do this sort of assessment for individual houses every day, so we thought we’d present some analysis of our database of Home Energy Masterplans. This produced some graphs which we found interesting, and so thought we’d share them.

In these graphs we aren’t showing individual measures (e.g. boiler upgrades, changing fridges or installing different showerheads), but whole packages that we put together for each client based on their timescales, budgets, ambitions etc. Our recommendation packages are categorised on some of the graphs below: recommendations are usually chosen based on payback of component measures (eg No Brainer < 5 years, Some Consideration 5 – 15 years, Green Halo 15 – 25/30 years) but we also make recommendations based on individual client priorities as requested (e.g. CO2 reduction cost effect, or budget available).

If you are thinking of commissioning a masterplan these charts will show roughly what sort of results you might expect, or also for those looking more strategically they might help you see the scale of savings might be possible for a given budget. The charts may also be useful for those thinking about or planning for the Green Deal.

For each graph we’ve added our thoughts: we’d very much appreciate your thoughts and comments too.

Here is a simple graph showing the paybacks of different packages. As we only build packages that have reasonable paybacks the results are as expected – low cost packages have quick paybacks. What this doesn’t show is that low cost packages will have lower total savings too.

This graph shows the CO2 savings for different packages. There is an overall trend that the more you spend the greater the CO2 savings.

So here we are trying to show the cost effectiveness of each package in terms of CO2 reduction. The lower the £ per CO2 the better. Its hard to get much out of this one other there is a much greater spread as the overall cost increases. A lot of the ‘Others’ are around the £10,000 as many refer to packages based on a £10,000 loan scheme. Perhaps the key message is that a strict financial budget approach may not be the best as you may end up spending money on things that are not all that cost/CO2 effective just to spend your budget.

This graph shows the percentage reduction in CO2 emissions that can be achieved for given packages. We’ve added a trend line too. It seems to show that for a spend of up to £20,000 you should be able to achieve reduction of between 40-70%. It also shows that the Government’s target of 80% if applied to houses is achievable but could get expensive.