Dork Scratchings

Dork Scratchings has finally decarbonised!  The first to go was the fossil fuel investing pension (this has been replaced by PensionBee's fossil fuel free plan ), then went the petrol car (replaced by an electric 208), and this week we got rid of the boiler. The new heating system is a Mitzubishi heat pump which heats water by extracting heat from cold air.  The laws of Thermodynamics set a limit on the amount of heat energy that can be produced per unit of electrical energy and the formula is $$ \frac{T_H}{T_H-T_C} $$ Where $T_H$ is the temperature of the hot water ($50^\circ C$ in our case), and $T_C$ is the temperature of the cold air outside the house.  Note that the temperatures have to be in Kelvin to make this work, and the value drops as the outside temperature drops.  For example, for $50^\circ C$ water, it is 12.9 when the outside temperature is $25^\circ C$ but only 6.5 when the outside temperature is $0^\circ C$.   The heat produced per unit of electrical energy for a r

In this post I argue that economic growth is not the normal state of affairs, it is a blip caused by the discovery of a one-off resource of non-renewable energy.   The logistic equation $$ \frac{dy}{dt} = y(1-y) $$ Here's a simple model.  Humans discover an exploitable but limited resource and start consuming it.  The amount consumed, $y(t)$, is a function of time.  The general form of the equation is $\frac{dy}{dt} = \alpha y (\beta - y)$, but if you choose the right units $\alpha$ and $\beta$ both become $1$. Why should this work, in principle? Early on, the factor $1-y$ is approximately $1$ and can be ignored.  So the model states that annual consumption $dy/dt$ starts off proportional to $y$.  In other words, $y$ grows exponentially at first.  This could happen if exploiting the resource enables further exploitation of the resource.  For example, suppose a few humans are shipwrecked on an island with 1000 trees: they take ages to cut down the first tree as they are using their

UBI stands for: Universal Basic Income The idea is pretty simple - it's a benefit$^*$ that is given to everyone (hence Universal) and provides enough to live on (hence Basic Income).  It's very much en vogue with economists at the moment but it tends to be received badly by voters .  "Why should millionaires get benefits?" they ask.  In this post I'll explain why I think they should! Imagine a country in which benefits are means tested, so that a citizen with no income receives £10K, but loses 50p of it for each extra £1 of income up to £20K.  After that they receive no benefits and start to pay tax.  The tax rate is a smooth curve that starts at zero, grows to 25% of a £40K income, 30% of a 50K income, and 40% of a 100K income.  That sounds fair. In the country next door there's a flat 50% tax rate on all income, and a £10K universal basic income.  Taxing people with barely any income at the same rate as higher earners and giving millionaires bene

I was never really that interested in economics until after 2008 when suddenly technical terms like structural deficit started appearing in the news.  Oddly, with anything relating to macro economics, journalists have to pretend they were born understanding all the concepts perfectly and they're not going to patronize you by explaining them.  This is in stark contrast to anything related science where they have to pretend to understand even less than they do!  Somehow this attitude has leaked out to the wider world, so that friends and colleagues down the pub - or politicians on Question time - will b******t eternally about the effect of interest rate rises, but happily or even boastfully admit to knowing nothing about how the rest of the universe works.  I, on the other hand, knew I didn't know anything about economics, but thought it was less important than all the other stuff I didn't know.  But when economics stories started to become the main content of the news rathe