It has been more than fifteen years since I lead the team responsible for Sainsbury’s at Greenwich, the UK’s first low energy supermarket, and you would have thought that things would have moved on significantly; but I am not sure that they have!
|Sainsbury's Millenium Store|
When we were developing the design of that building in the mid 1990’s there was a clear philosophical intent that drove the design process. We wanted to achieve a building that halved the energy required to operate it compared with a standard store; but crucially to do this in a manner that would create a more comfortable and well tempered environment for both customers and staff.
These human factors are important because we had a hypothesis that if you make people feel comfortable in an environment then they will relax and be willing to spend more time within the building. This creates the opportunity for the retailer to be able to make more sales per visit and these additional sales have a dramatic effect on the financial performance of the store, significantly outweighing the additional costs incurred in delivering the performance upgrades.
As the design developed we gave considerable thought to what factors would influence customer’s perception of comfort and sought to optimise each one.We started with natural lighting and the provision of views out from the interior to the external environment, since many people complain of feeling claustrophobic in larger retail units because they provide no visual connection to outside. The north light solution selected not only provides views out but also floods the store with natural daylight and is fact an adaptation of art gallery daylighting which has been specifically developed to display their “products” to best effect.
|Internal Environment Flooded With Natural Daylight|
When it comes to heating and cooling the space the decision was taken to remove all air conditioning as this is energy intensive and can cause discomfort because heating and cooling is delivered directly on to customer’s heads! Instead the store floor was designed as an enormous radiator; incorporating underfloor pipework that gentle warms or cools the sales floor. The energy for this process was derived from two sources, an onsite combined heat and power plant providing the heating and a borehole the cooling.
The final element that helps make the space more comfortable is the ventilation system. In more traditional designs fresh air is introduced at high level with fans blowing it down onto the people below. The problem with this arrangement is that the fresh air is mixed with warm, stale, moist air that collects at ceiling level, so that customers never get to breathe clean fresh air. To address this issue we brought air into the store from beneath the floor, delivering it directly into the zone that customers occupy and preventing it getting polluted en route.
The completed building celebrated its ten Year anniversary last October, so what developments have been made in the sector since then?
As a number of “eco stores” have been completed by most of the other major food retailers, it is clear that the project has driven change. However, what is surprising is that the focus of these subsequent stores is solely environmental innovation almost to the exclusion of all other factors. Systems that have been incorporated that undoubtedly reduce energy consumption but which do little or nothing to improve the customer experience.