Ridgeway Solar

A closed domestic landfill, capped in 1978 to a standard nobody would accept today, with a gas monitoring record that had been kept diligently and read by almost nobody. Solar on a capped landfill is an attractive proposition — the land has no agricultural value, the grid connection was already close, and the alternative use is nothing — and the entire consent turned on whether the cap could be left intact.

It could, with a ballasted mounting system rather than driven piles. That decision was made in week two and it removed the need for any ground penetration across 22 hectares, which in turn removed the objection the Environment Agency would otherwise have raised about creating preferential pathways for landfill gas.

We re-interpreted eleven years of gas monitoring data and found what the annual reports had not commented on: methane concentrations in three perimeter wells rose consistently after heavy rain, consistent with a perched water table displacing gas rather than with cap failure. That distinction was the difference between a scheme and a remediation project. We recommended two additional monitoring wells and a revised trigger protocol, both of which were conditioned.

The ecology was straightforward — the capped mound had developed a decent calcareous grassland sward, which we protected with a lower panel density on the south face and a skylark plot. Glint and glare modelling cleared the local aerodrome without mitigation. Total time on those two: three weeks. The gas work took five months.