You probably know how warm sewer pipes are when it's cold outside. Here is a quote we received from a former wastewater utility manager; "Anyone who has ever performed confined space entry into a sewer during the winter months, understands the value of this heat. Team members would often argue about who would get to go into the warm sewer and who would have to stay topside and freeze."
The constraint which is rapidly becoming critical for us all is time. A good analogy is the famous 'square peg in a round hole' scene from the Apollo 13 movie, where CO2 levels in the spaceship were reaching dangerous levels (sound familiar?). The managers threw a collection of items on the table and staff were told to come up with a solution because time was limited. It's the same situation here on our spaceship (Earth) where we are in space and CO2 levels are reaching dangerous levels. The collection of items we have available are: people, equipment, money, limited energy and limited time. Failure is not an option!
Decarbonisation of cities will require require a large shift to electrification for heating buildings, but transportation is also shifting to electrification. So city energy planners have a competing demand. City electrical supplies and distribution networks are coming under increasing pressure to cope with these shifts and changes in demand. And time keeps ticking away....
But cities have wastewater networks collecting and carrying huge amounts of free low grade heat. This heat energy is reliable, predictable, stable and already where it is needed by buildings, and your infrastructure that is collecting and transporting this heat is already constructed (the sewer network). Your heat energy is sadly invisible, so it is just ignored and flushed away every day. The favorable temperatures of wastewater allow wastewater source heatpumps to operate more efficiently than air source heatpumps. So when buildings capture and recycle wastewater heat using heatpumps, it allows them to stop burning fossil fuels and electrification of more buildings to be achieved using less electricity (so helping manage the growing demands on the electrical infrastructure). Win/Win/Win for the environment, the buildings and electrical authorities.
A view over a wastewater treatment plant during cold ambient conditions.
The amount of thermal energy available within wastewater is enormous.
Typically 20%-35% of total housing energy + up to 40% of low temperature heat used in commercial & industrial sectors gets turned into hot water, which then goes into a city's sewers.
So there are enormous amounts of low carbon heat available in every city's wastewater network.
This energy flows through pipes which are already constructed and they are located in the city (where heating & cooling energy is needed).
But this energy is invisible and tragically normally simply flushed away everyday.
For a sustainable world, we need to stop this energy waste and recycle the heat.
We can help with mapping the heat in your wastewater networks. You can already see cities which have had their wastewater networks heatmapped on our global map. These cities are: Christchurch - NZ, Dunedin - NZ, Nelson - NZ and we want more! Click here to have a look. With this information you suddenly have a very valuable energy resource available to offer. With a map, you will know how much heat energy is available and how it is distributed throughout the city. And this heat energy and the collection infrastructure is available today, time is not a constraint to utilize it.
The Water Research Foundation Report 'State of the Science and Issues Related to Heat Recovery from Wastewater' says this about wastewater network heat mapping: "The mapping process is an essential tool for policy makers. It allows the governing community and the
developer community to conceptualize the resources available and how to connect them to needs."
We can help with education and training. We have a network of experts in North America, Asia, Europe, Scandinavia and Australasia who can provide presentations, training courses etc. to
We can help by providing technical support. Our experts can provide engineering and mapping support with things such as:
As a wastewater utility, you control the wastewater network and the heat energy flowing within it. You can raise awareness of this energy resource. You can give access to the heat and allow building owners & designers to utilize it. You can open the doors and welcome them as new customers for your energy.