Population

 

Understanding Global Warming

Human Population and Energy

The sheriff enforced Oct. 2019 the largest emergency evacuations in Santa Rosa as the Kincade Fire continued growing. Santa Rosa was hit hard by the Tubbs wildfire that destroyed thousands of homes and killed 22 people two years ago. A swarm of fires burned almost identical areas of Napa and Sonoma counties in September 1964, 53 years ago. Despite burning tens of thousands of acres, these fires did not cost any lives, partly because the area was less inhabited than it is now. There have always been wildfires in California, and nothing indicates things have changed - only the damage is growing with increasing population density.

Current World Population is 7.741.000.000 with an annual growth rate of 68.000.000. This increases the impact of natural disasters often incorrectly interpreted as caused by increasing extreme weather.

With a worldwide per capita energy consumption as in Denmark (134 GJ/capita), the present annual world demand 0,4 million PJ goes up to one million PJ. Acc. to IPCC there is 1-2,000 Gt Carbon in the fossil pool equivalent to 25-50 million PJ – hyperlink – equivalent to IEA estimate of 49 million PJ proven reserves. The gradual depletion of resources will within a foreseeable future create a proftable market for renewable energy in which electricity is preferably used in stationary applications and methanol in mobile devices.

Figure 1. After 10 years of constant population in the 1980s, the population began to grow strongly in the early 90s

Population figures in Denmark before the first census 1769 are very uncertain. There is archaeological evidence, that the population of the area now occupied by Denmark was around 500,000 in the year 800 AD - hyperlink.  This steadily increased until the 1200s, when the population reached app. 1 million - again falling during the less fertile Little Ice Age.

This indicates a Danish population of one million as just sustainable by agriculture.  Energy imports in the form of feed and fertilizer from North and South America enabled population growth after 1750 - later enhanced by the introduction of fossil fuels. By supplementing photosynthesis with present level of renewable energy the sustainable Danish population has been doubled to about two million since 1750.

Human overpopulation occurs when the ecological footprint of the population exceeds the carrying capacity of the land. This is traditionally related to food, but lately also to renewable energy. With present Danish fertility rate of 1,71 and no immigration the Danish population will decline and reach sustainability in 200 years. With a South European fertility rate of 1,33 it will take less than 100 years. With present immigration the Danish population will incline forever.

Population Policy

Very few countries have or have had a policy of a desirable or sustainable population density. A pre-industrial population density could be a sensible and achievable goal. Our agriculture will always be able to feed a population of that size and without the supply of energy from outside. At the same time, it would significantly reduce the environmental impact. With current fertility we will be able to reach such a goal in100-200 years.

The business community's insatiable need for labor tempts to invite guest workers who, however, are assimilated in just a few years and only contribute to increasing the population. At times, even child abundance is rewarded.

From the post-war years with approx. 150,000 to date, the number of civil servants has more than quintupled; especially in the period 1965-83, the increase was sharp. Instead of guest workers, it will be relevant to assess whether the sharp increase in the number of public employees is appropriate and necessary. 

Are we happier now than in the 1960s? Society also functioned then. It will still do so, even though half of the public employed took jobs in the business world that misses them so much?

Energy Procurement.

Weather makes heating our homes needed. Despite our high latitude, about 120 kWh of photovoltaic energy can be produced per m² in Jutland. It is windy and newer turbines generate on an annual basis 4.100 MWh (14,8 TJ) per installed MW ~ 47% efficiency. Even in Denmark solar photovoltaic has a future – Irena 2019.

DK Transportation Fuels. 

Denmark consumed 2018 total fuels 8.717.000 m3 (307 PJ) – hyperlink. 3% are renewables of all fuels for land, sea and aviation.

Our total gross energy consumption 2018 is 778 PJ/year ~ 134 GJ/person (37.200 kWh/person). The renewable energy is 33% - hyperlink. To achieve sustainability, the production of renewable energy must triple. Just in order to keep pace with population growth we must erect a wind farm like Krieger's Flak every three years.

EU 2030 32% Target.

We have already 2018 reached the EU 32% target of all energy as renewable – hyperlink.

DK 2030 55% Target.

The Danish target of 55% in 2030 will be hard to reach – hyperlink. It requires more than halving the current consumption of coal, oil and gas and replacing this with at least 186 PJ from new wind turbines. Conversion of surplus electricity to electrofuels will require doubling for the proportion being converted - hyperlink.

The biggest shortcoming of solar and wind energy is the lack of temporary storage. This need becomes increasingly urgent as the renewable energy is expanded. Temporary chemical storage as methanol is advantageous because it may be used for transportation as is with no need to reverse the process.

Extra wind power to compensate for conversion energy loss for electrofuels is ignored due to their increased range. A fuel cell doubles the range of methanol.

DK 2050 100% Target.

It will require 60-70 new wind farms the size of Kriegers Flak to replace all fuels with electrofuels - comprising ⅓ of the Danish sea territory (Total: 25,000 km²). Kriegers Flak 605 MW covers 132 km², produces 2½ billion kWh/y (9 PJ) enough for 4½ PJ methanol. Doubling that number and using high winds for methanol and low winds for the rest will just phase out all fossil energy. Such a 100% target for phasing out all fossil fuels seems out of reach.

Since 2015 our energy consumption has been increasing. We will have six data centers in 2030 - and nine in 2040 consuming 25 PJ and 41 PJ, which corresponds to 20 and 33 per cent of total electricity consumption for 2017. Answer to Parliament 2017. Bitcoin Energy Consumption is another new application. So, savings are not in sight - hyperlink.

105 Octane M85

The project IEA-AMF Annex 56 Methanol as Motor Fuel proved 105 Octane M85 suitable as a replacement for gasoline for an ordinary petrol City Car - hyperlink. A larger fleet trial is in the pipeline - hyperlink. The figure left illustrates the phasing in of the new motor fuel along with electricity. The present production capacity of close to one million ton of methanol a year will meet the demand until 2027 where new facilities/extensions will add up.

The project IEA-AMF Annex 56 Methanol as Motor Fuel Phase Two focuses on M85 (85% methanol) for existing petrol cars. Our next test car will be an electric car with a small 15 kWh battery (vs 65 kWh in the dedicated all electric version). A Danish add-on methanol fuel cell gives it a range of 1000 km. Methanol can also be used in heavy-duty vehicles that traditionally use diesel. Scania’s new 13-liter truck engine runs on alcohol ED92 or MD92 and Stena Line has demonstrated the usefulness of methanol in ferry operation.

Understanding Global Warming, Oversigt - LINK