After a taxing day in Nairobi working to finalise a declaration of African faith leaders on climate change, it was good to take a break and a tour with some senior African clergy of an amazing new office building constructed here on the UN’s Gigiri compound to house staff of the UN Environment Programme. (Our SAFCEI/AACC/Procmura conference was kindly hosted by UNEP.)
The new building accommodates 1,200 people and on its roof, six thousand square metres of solar panels generate more power, on average, than the building consumes, also powering other neighbouring buildings, and feeding power back into the local grid. At night, or when it’s cloudy, it uses grid power.
(The Kenyan grid runs off 50% hydroelectric, 16% geothermal and 33% oil. But the country plans a substantial increase in geothermal generation, as persistent crippling drought – climate change – threatens the hydroelectric supply, and the continent’s largest wind farm will be completed at Lake Ngong in 2012 to supply a quarter of the country’s power.)
In seven to ten years time, the UNEP building’s solar PV power system will have paid for itself, and be making money for the UN.
Most of the lighting is natural, with light wells on the roof that drop illumination through successive glass floors. Artificial lighting is not yet LED-based, but with no light switches and presence detection, the lighting bill is already 70% lower than it would be for an equivalent older building.
UN Security wanted to install floodlights around the building. The designers said no. They pointed out that any time someone’s in the building, one of the infrared-sensitive low power lights goes on. The security people have come to rather like this feature.
The central atrium is a thoroughfare, light well, cooling chimney and ventilator. The complex has four atriums, each with a different micro-landscape mimicking Kenya’s four main botanical systems: desert, forest, coastal and savannah.
Someone did whisper to me that the building’s rather hotter in summer than is really comfortable, but perhaps this will improve as the building’s managers fine-tune the existing systems. Alternatively, maybe UNEP should just send its staff home, or take a siesta, on those days, in accord with the “let’s all just slow down” sustainability principle.
All rain water is collected and all waste water treated on site, in a South African-designed closed biological purification system, to the point of being drinkable.
A typical basement server room would have cost UNEP $100,000 a year to cool using aircon. Instead, they opted for an outside smart-ventilated server unit supplied by Microsoft that uses one twentieth of the power with air and water cooling (it’s an ITPAC – IT Pre-Assembled Component). “Pity it’s so ugly,” I commented, rather rudely. All computers used are laptops, using a third of the power of desktops.
All these efficiencies mean that total power usage is a quarter of that of older, neighbouring buildings.
Around the building, access by heavy vehicles is on reinforced but grassed-over drives that are far easier on the eye, and cooler, than paved lanes.