The challenges of reducing
(written for Energy in Buildings & Industry)
Sourcing, installing and measuring the performance of energy efficiency
technologies can be a complex process. David Bakst, Operations Director at
Sabien Technology outlines the key things to do well in order to reduce energy
consumption and CO2 emissions.
The majority of organisations we speak to are looking for proven solutions to
fast-track their reductions in CO2 emissions and energy consumption. And very
often the energy manager will be responsible for identifying such opportunities,
evaluating potential solutions, managing roll out, validating results and
reporting back to senior management. All of which brings potential complexities
As a company that has built its reputation in project managing the installation
of its own patented energy efficiency technology, M2G, we have accumulated
considerable knowledge and experience of running nationwide multi-site
installation programs. While our methodology and approach is specific to our
technology, the underlying philosophy, I believe, can be adopted for other
technology roll out projects.
In fact, energy monitoring and targeting specialist Vilnis Vesma also advocates
the methodology that we have developed for our projects, as he explains: “If you
are trying to prove the savings you have achieved through an energy project, the
question you have to answer is simply this: how much am I now using, compared
with what I would have used in the absence of the project?”
In the case of a heating system, for example, this approach requires a
methodology that takes account of both day-to-day variation in ambient
temperatures and any variation in demand resulting from activities in the
building. How to achieve this is discussed in more detail later on, but it’s
important to take such projects step-by-step.
So, before you get started, you need to base-line your energy consumption and
understand how much energy you are consuming. With the Carbon Reduction
Commitment (CRC) coming into force in April 2010, it’s vital that CRC-qualifying
organisations can accurately calculate and report on their CO2 emissions. This
then starts to identify potential ‘quick win’ solutions (behavioural or
technical), with proven fast paybacks (usually within two years).
Having identified the areas of focus it’s now necessary to identify potential
solutions, perhaps by talking to peers at networking events – which also helps
to build a picture of potential suppliers. It’s also useful to understand how
each product applies itself to your specific set of issues, ideally backed by
third party client references. Suppliers should also provide a forecast on the
level of savings that can be expected, bearing any variables in mind.
Another important issue is to ensure that any such works will not impact on
comfort conditions in the building(s).
Evaluating the success of any such project depends on the amount of energy
reduced and the payback period; measuring this is complex. Automatic meter
reading (AMR), for example, will measure the total volume of energy being
consumed by the building or site but not the energy consumed by individual items
Installing sub-metering is one solution to verifying energy consumption at plant
level, but it is expensive to implement. To overcome this approach, we have
developed a ‘toggling’ technique for our specific technology that switches
between running the M2G one day and then bypassing it the next, usually over a
period of one month. The result is a comparison of ‘with and without’ an energy
saving device – thus taking account of demand variations within the building.
This general principle can also be applied to many other types of energy-saving
However, as noted earlier, in the case of any heating system there will still be
temperature variation from one day to the next, so these figures need to be
adjusted by using degree day analysis, which helps account for the effects of
weather on energy consumption. Where more precise evaluation is required, degree
days for the region can be replaced by an onsite temperature data-logger.
In addition, the changes in energy consumption over longer periods of time (pre,
during and post project) can be established by CUSUM (cumulative sum) analysis,
a Carbon Trust-approved tool that examines trends for sequential events, such as
energy consumption, over time.
In parallel with accurate measurement, it’s important to ensure that energy
reduction initiatives are carried out one at a time. If there are two projects
running simultaneously for the same energy source, for instance, it will be
virtually impossible to determine which is responsible for the results by using
Similarly, it’s important to be aware of other changes in the building that
could impact the results. These include changes in the occupancy and occupant
behaviour, changes to the building fabric, plant failure, changes to equipment
configuration and, surprisingly, disablement of the new energy saving device by
others who may not have been privy to the programme in the first place.
I can’t emphasise just how important it is to include all stakeholders in the
process. They’ll appreciate your consultation, respect you for doing so and it
will go a long way to helping you achieve technology adoption throughout your
chain of influence.
We have also recognised that, with the current focus on energy efficiency, most
energy managers aren’t short of things to do and we believe there is an onus on
the technology supplier to manage as much of the project as is possible. In a
recently completed estate wide roll-out of M2G at AVIVA, for example we managed
the project from start to finish. The client simply provided us with details of
the relevant site contacts and we took it from there, ensuring every stakeholder
was briefed on the project and our terms of reference of the same.
The majority of the factors mentioned here will apply to most energy savings
projects and, in our experience, addressing each of these issues in advance will
help to ensure a smooth implementation and the most cost-effective solutions. As
well as AVIVA, this methodology has proved effective in projects with
Communities & Local Government, , Jones Lang LaSalle, Serco, the Institution of
Mechanical Engineers, Bradford Metropolitan District Council, Nottingham City
Council,O2 and many more.
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