We Need to Rethink the Way We Heat Ourselves. Here's why

View Only

We Need to Rethink the Way We Heat Ourselves. Here's why

By District Energy posted 08-21-2019 15:43

Recommend

Weforum.org

Summary

Half of our total energy consumption globally is used for the production of heat - for our homes, industrial purposes other applications. Most of this heat comes from the burning of fossil fuels such as coal, and is responsible for a significant proportion of world pollution.

However, to-date we have seen very little progress across the world in cleaning up how we generate heat - despite the existence of more sustainable and cost-effective solutions. A major reason for this is that the heating systems we have built across much of the world are both costly and troublesome to change, and there are whole piles of government incentives that favour fossil-fueled alternatives. That said, there are lots of environmental pressures which are forcing change - starting with air quality in cities like Beijing and Delhi, as well as global pressures to decarbonise.

Heat’s complexities begin with its physics. Heat is all about the flow of energy and works in three different ways: by convection, by conduction and by radiation. Heat is also governed by two important scientific laws; the first and second laws of thermodynamics. The first law states that energy can not be created or destroyed but just goes from one form to another; the second law states that it is impossible to convert one form of energy to another without some form of heat loss. Some of the greatest losses occur when oil and gas are converted from chemical to heat energy to power an internal combustion engine or a turbine. It is thus critical to either reduce the level of waste heat or to capture that heat for other purposes.

There are many ways to reduce waste heat such as building better-insulated buildings or increasing the efficiency of engines. Another way is to capture and use the waste heat for other purposes such as heating hot water, which can then be used locally in a district heating system. Such systems are costly and take time to build - however, the digitalization of our world is providing us with a massive opportunity to rethink heat, and where we get it from.

Full Article

#News
#DistrictHeating

2 comments

9 views

Permalink

Comments

Robert Benz

08-24-2019 11:29

Electrifying heat either directly or via heat pump is a great concept, were it not for lack of electrical infrastructure and economic wherewithal to construct the needed lines substations and power supply to implement the strategy. The University of California system has mandated the complete shift away from "fossil fuels" which will require just one campus to construct an additional 40megawatt feed, replacing the 7700btu/kw-hr heat rate CHP with PG&E power substantially generated during nighttime via 11000+btu/kwh turbines at an added cost to the University (Student tuition) of $30million per year. Obviously, a fair amount of gas turbine peaker power could be reduced through electrical storage, but without added costs and not before the 2025 mandated deadline arbitrarily set by the UC directors. So in the quest for the zero carbon future, the University of California system will be simultaneously increasing atmospheric carbon loading while increasing the cost of higher education.

Meanwhile there are immediate and substantial decreases in CO2 emissions that can be had just by increasing existing efficiency of steam plants and fixing gd leaks! A few years ago, all the buildings steam lines were shut down yet the same UC University steam plant was still shipping out over 20klb/hour of 150psig steam! Ego leaks = ~30mmbtu/hour = 12,000mtons of CO2/year. A certain steam plant in the North East is generating 600klb/hour 200psig steam but only shipping out 400klb/hour steam - over 80k tons of CO2 per year at a cost of ~$4million/year.

There's nothing wrong with promoting an all electrical future, but if the folks dreaming these systems up truly believe that the increase of atmospheric carbon represents the existential threat it is, orders of magnitude greater reduction in CO2 emissions can be had, years if not decades before implementing electrification concepts just by increasing the efficiency of existing steam systems.

Thomas Phelps

08-22-2019 11:30

The author's 'heart is in the right place' in advocating district energy as a more efficient domestic heating alternative. However, after quoting the 2nd law of thermodynamics,  Mr. Reid then shows he does not understand its strong influence over electric power costs. Instead, he implies that government regulations, taxes, and 'incentive structures' are largely responsible for fossil fuel energy being much less expensive than cleaner electricity, and therefore preferred by many. Wrong!
If he were correct, changing these allegedly wrong-headed incentives would be achievable. Changing physics and the resulting economics is more difficult.
While there are policies that need attention to remove disincentives to greater heating efficiency, clearer thinking and a more accurate aim is a prerequisite to policy changes. Tilting at windmills is a waste of time.
Tom Phelps, P.E.

Industry News