No Home Left Behind: A Summary of Prof Andrew Crossland's Presentation

The core argument 

Andrew opened with what he called a deliberate provocation. The conventional view holds that flexibility (the ability of smart home technology to trade energy with the grid) is the magic ingredient that makes domestic decarbonisation financially viable, manageable, and attractive. He then spent the rest of the session systematically dismantling that assumption before rebuilding it on firmer ground. 

His thesis: we have the technology. We have the capital. What we do not have is a delivery model that reaches the 14 million households sitting in the missing middle of the market: people who want solar, do not qualify for subsidy, and cannot justify a large upfront payment. 

Why climate action fails at the household level 

Andrew framed the problem in terms of social licence. Net zero targets are proliferating globally, covering 88% of emissions, yet technology adoption in homes lags badly. The reason, he argued, is that policy focuses almost entirely on either the poorest households or those already able to pay, leaving the largest group entirely unserved. 

He drew on S-curve adoption theory to make the point: technology only reaches everyone when it reaches the missing middle. Citizen-led adoption is faster than top-down mandates. He cited the striking statistic that in 2023, households in Pakistan installed more solar than the UK has in a decade, as evidence that demand is not the limiting factor. 

He also connected home decarbonisation to wider social crises. Cold and damp homes cost the NHS billions annually. Energy costs hit the poorest hardest. Without people feeling the tangible benefits of the transition now, in their bills and in their health, public trust and political support will erode. 

The six barriers that must all be solved together 

Andrew's framework identifies six interconnected barriers. Treating any one of them in isolation, he argued, will not work. 

Social. 18 million UK households want solar, but only 4 million are willing and able to act at current price points. Subscription models have been shown to treble uptake by removing the upfront cost barrier. The New Zealand SolarZero model demonstrated this across all demographics, including social housing tenants. 

Financial. High cost of capital is the single biggest kill-switch for subscription models. The economics work at 5% debt, break even at 8%, and collapse above 10%. Government credit guarantees and first-loss capital are the lever that makes the model viable at scale. This has already been validated by three major international accountancy firms and tested against 30,000 social housing tenants in the UK. 

Technical. Battery costs have fallen more than 90% since 2010. Solar and storage combined can now meet 60 to 70% of a home's annual electricity demand, with payback periods of four to seven years and still falling. But installation costs lag behind equipment costs, and 42% of IEA net zero savings still rely on technology not yet deployed at scale. Andrew also noted that east and west-facing roofs often outperform south-facing ones, and that myths like this must be actively corrected. 

Institutional. Standards, export payment delays, Smart Export Guarantee reform, and network registration failures all act as friction. Andrew co-wrote the MCS standards that govern savings estimates and called for a Citizens' Charter: a principle that every citizen has the right to access, connect, and benefit from low-carbon technology in their home. 

Grid. 3,000 GW of renewables are stuck in grid queues globally. Price cannibalisation and curtailment are already hitting solar returns. Andrew's view is that poor grid codes, not technology, are the real bottleneck, and that 5 million solar homes in the UK could reduce the required wind build-out by 5 to 10%. 

Cyber. Millions of internet-connected inverters create millions of attack surfaces. The collapse of GivEnergy (with 70,000 UK installs affected) illustrated the supply chain fragility. Andrew argued that cybersecurity must be built into subscription contracts and MCS standards, and that this is an engineering and institutional problem, not just an IT one. 

How subscription models actually work 

The session walked through the subscription model in practical terms. A provider installs solar and battery at no upfront cost to the household. The householder pays a monthly fee, typically £50 to £55 at government-backed debt rates of around 5%. Monthly savings run at £65 to £80, meaning the household is in a net positive position from day one. After 15 to 20 years, the system is owned outright, delivering approximately £840 a year in ongoing savings permanently. 

Andrew was candid about the failure modes: high-margin businesses cannot hit the price points needed; relying on virtual power plant revenues to make the savings add up is fragile; battery warranty risk can strand customers if the provider fails. These are solvable problems, but they require deliberate design, not optimism. 

What flexibility actually does, and what it doesn't 

The reframing of flexibility was one of the most intellectually interesting parts of the session. Andrew argued that flexibility is volatile, can destroy energy businesses if mismanaged, and has low value on a per-home level when treated as a revenue stream in its own right. 

What flexibility can do, if properly structured, is act as a silent optimiser. The battery discharges at peak times, the EV charges overnight or on solar, the heat pump uses off-peak electricity. The household never needs to engage with energy markets. The technology does the work. The value is realised through a tariff and an optimiser, but the financial unlock comes from somewhere else entirely: cheap, long-term debt. 

The ask of government 

Andrew closed with three specific interventions he believes are necessary. 

• First, credit guarantees and first-loss capital to enable long-term debt at around 5%. Without this, the subscription model is financially unviable regardless of how good the technology is. 

• Second, a meaningful Smart Export Guarantee tariff. The current level is set close to zero, which removes the export incentive that makes the economics more robust for households and providers alike. 

• Third, adoption of the Citizens' Charter, enshrining in policy the principle that every citizen has the right to access, connect, and benefit from low-carbon technology in their home. 

His summary was deliberately simple: solar and batteries in homes are right for the network, right for the 2030 climate targets, and right for citizens in terms of bills, fairness, and public trust. The barriers are real but solvable. The model is proven. The missing ingredient is political will, specifically the willingness to use government's balance sheet to bring down the cost of capital. 

Prof Andrew Crossland can be reached at andrew.f.crossland@durham.ac.uk. His work is also published at afcrossland.substack.com and mygridgb.co.uk.