Showing posts from June, 2019

Local Authorities and Climate Change

Many local authorities in the UK have committed themselves to timetabled action on climate change. According to Hilary Lamb [1], in November 2018 Bristol City Council became the first principal UK authority to declare a climate emergency in the UK, pledging to aim for net zero carbon emissions by 2030. Other cities with similar targets include London, Manchester, Lancaster, Leicester, Nottingham, Oxford, Durham, Sheffield, Cambridge, Plymouth, York, Sunderland and Newcastle. The city authorities have been joined by many town, parish and district councils in pledging to sharply reduce their carbon emissions on similar time scales. More recently the UK parliament passed a motion making it the first in the world to declare an “environment and climate emergency” [2], and this has now passed into law as an amendment to the 2008 Climate Change Act. In the context of these commitments, the focus of this post will be on the scope available to local authorities to take action.
A report publishe…

New York’s REV and UK policy

A recent discussion paper from a UK energy policy group describes the current governance of UK energy as confused, with advisory and regulatory bodies which have different objectives, and are concerned with different aspects of the energy system. The paper analyses the present structure of governance, and makes recommendations for reform. The model of governance recommended is that of New York State’s Reforming the Energy Vision (REV) initiative, which describes itself as concerned with renewable energy; building and energy efficiency; clean energy financing; sustainable and resilient communities; modernization of energy infrastructure; innovation and R&D; and transportation [1].
A paper on the REV initiative by J. D. Makholm [2] reports that important aspects of the project drew inspiration from the UK. In view of the above policy group recommendation, this claim invites examination. New York has pursued the REV initiative since 2014. Makholm describes it as borrowing often “from …

Measuring Air Change Rates by CO2 Decay

A method and its limitations
The three preceding posts have been about minimum safe levels of air change, types of indoor air pollutants, and ways of estimating air change rates. The last reference was to a method based on monitoring the decay of indoor CO2 levels in a room or building [1]. This method and its results will be examined here in more detail. The concept is straightforward: CO2 is produced by the occupants of a space over a suitable time, and then they leave. Normal ventilation is maintained, and a monitor records the subsequent levels of CO2 in the space and in the incoming air. These data allow calculation of the air changes per hour (ACH).
The exact value of the initial level of CO2 is unimportant. Under a constant level of ventilation, the rate of removal of CO2 will be proportional to its concentration in the space. This defines an exponential decay, tending to equilibrium when CO2 concentration in the space matches that in the incoming air. Monitoring must continue …