Ealing earned the nickname "Queen of the Suburbs" for a reason: the borough is built substantially from planned Victorian and Edwardian garden estates, and that inheritance shapes both its planning regime and its retrofit economics.
Ealing has around 32 conservation areas, of which 6 carry Article 4 directions affecting householder alterations. These are concentrated in the borough's planned estates — Hanger Hill Garden Estate being the best known — where the council has removed permitted development rights specifically to preserve a deliberately uniform architectural scheme. On estates like these the objection to solar is usually about visual consistency across a designed terrace or crescent, not the panels themselves.
The remaining conservation areas operate under standard national rules, which means rear-slope solar is generally permitted development. Ealing also has a borough-wide HMO Article 4 direction that doesn't affect renewables.
Ealing's Edwardian and inter-war semis are close to ideal heat pump candidates by London standards: detached and semi-detached plots with real side returns, so the 1-metre boundary rule that frustrates inner-London terraces is rarely the blocker here. Gardens are generous enough that siting is a design choice rather than a constraint.
The catch is fabric. Large Edwardian villas with high ceilings, bay windows and often solid walls have substantial heat loss, and a heat pump sized for an uninsulated version of that house will be both expensive to install and expensive to run. The heat-loss survey matters more here than almost anywhere — and if the survey flags solid walls, understand that internal or external wall insulation is a far bigger and more disruptive job than the loft and cavity work covered in our insulation guide.
For solar, the garden-suburb layout is a genuine advantage: wide plots, generous roof areas and comparatively little overshadowing from neighbouring buildings compared with terraced inner London.
For costs, grants and how the national rules work, see the heat pump guide, solar guide, air conditioning guide and insulation guide.