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In every 1 million Btu's of combusted natural gas are 5 gallons of recoverable ~ distilled water.



Last year in America approximately 19 Trillion cu.ft of natural gas was combusted at larger commercial buildings, by industry and America's power plants. All natural gas appliances have a chimney, and going up all these chimneys is the combusted exhaust which is made up of heat energy that did not make it into the process, and CO2, and water.

In order to create the condensation (water) the heat energy has to be removed from the combusted exhaust. This is done with the Sidel SRU Flue Gas Condenser. These stainless steel and aluminum custom constructed units are designed to very efficiently transfer the heat energy that is in the combusted exhaust into water that can then be utilized back in the building or facility.

As the heat energy is being recovered and the exhaust temperature is reduced to well below the temperature of condensing, water is being created. The cooler the exhaust temperature is reduced, greater is the volume of water produced. It is possible to have the exiting flue gas temperature to be even cooler than the outside air temperature. When the temperature is lowered this much, water is flowing out of the base of the SRU unit. This water can be used as it is or be treated to be used for many other applications.

Commercial buildings and industry have different types and capacities of boilers. Some are used to provide hot water for building space heating or to heat domestic water. Typically these boilers range in capacity from 2 million Btu/hr up to 20 million Btu's /hr.                                              Depending on the industry their boiler capacities can go to 200 million Btu's/hr or larger. Power plants have much larger boilers that vent much larger volumes of combusted energy and exhaust and water into the atmosphere. The flue gas temperatures can range from 275 F up to 700 F. It is possible with the correct engineering to create applications to recover the waste heat and have these appliances operating at well over 90% energy efficiency.

What actions do you propose?

America and the world is concerned about the effects that climate change is having. There are 3 main aspects to climate change that need to be dealt with. (1) Reduce Global Warming (2) Reduce CO2 Emissions (3) Conserve Water.

By increasing natural gas energy efficiency, all 3 of these steps can be realized. The US Department of Energy states that for every 1 million Btu's of heat energy that is removed / recovered from the combusted exhaust and is utilized, 117 lbs of CO2 will not be put into the atmosphere. By not venting all of this waste heat energy into the atmosphere from all the natural gas appliances operating across the country, will greatly help to reduce global warming.

Companies and building owners are always looking for ways to increase profit margins, and increasing energy efficiency is one of those ways.    The water that is created from the combusted exhaust can be used in the building or facility, conserving water that would otherwise be brought in from the street or a well. This water could also be used to irrigate the lawns and flower beds, again avoiding the use of more expensive treated city water.

Cost of the SRU Flue Gas Condenser is relevant to the size of the appliance and the amount of natural gas that is combusted to meet the building or industrial process needs and requirements. Naturally the cost of the SRU equipment is related to the physical size of the natural gas appliance. In past sales the Return On Investment averaged somewhere between 2 to 5 years. The ROI was most often much faster on larger installations.

In the past we have had requests to assist companies to increase their energy efficiency where their internal operations would not blend with our SRU energy saving equipment. There was no application at these facilities to apply the recovered heat energy.

Very recently Sidel Systems has partnered with a company that has developed a Subsonic Bladeless Turbine. With this new added feature it is now possible to utilize the recovered waste heat energy and transform this waste heat energy into electricity. The very first installation will be completed by mid July, 2016. This project is being done without a SRU unit so there will be no water created, but engineering has been done for a few other installations with an SRU unit. Projections for an ROI will be 4 to 6 years. Again everything is relative to how much natural gas is being purchased from the utility monthly.

Who will take these actions?

Companies that want to be good corporate citizens and government agencies that have been told to look for methods to increase their energy efficiency and reduce their environmental impacts. More industries and retail companies are requiring that their supply chains show what they are doing to reduce their carbon footprint. Water is starting to become an increasingly more important issue.

Many states are starting to implement a Carbon Tax as a method to encourage industries to make a move forward towards increasing their overall energy efficiency. This tax should be on all buildings and industries, and not only on the largest of industries. I believe that if everyone is doing what they can to comply, they will also be looking at how they are comparing to others in their industry or locality.

Local governments must be setting the example. Hospitals and prisons and other large government buildings should be setting the example for others to follow.

Where will these actions be taken?

There are many countries around the world where today where drought is a major concern. In India and Vietnam wells are drying up and people are having to bring water home from much further distances. I was sent a email about a child who drowned in a bucket of water in their home.

Many countries combust natural gas, LPG or bio gas at their industries and electrical power generating facilities. Many of these countries have committed themselves this year to reduce their carbon emissions to help reduce the negative effects of climate change. Many of these countries could also benefit with the creation of water to meet their other needs.

There are many parts of North America that are also feeling the effects of  Climate Change. California and Alberta have both been in droughts for the past 4 years. In some parts of the country the land has been sinking due to over pumping of ground water. Collecting the water from combusted fossil fuels and injecting this water into the ground will help to  alleviate these problems.

How will these actions have a high impact in addressing climate change?

Last year American commercial buildings and industry and electricity producing power plants consumed approximately. 19 Trillion cu.ft of natural gas. Approximately 65% of all this combusted natural gas was wasted, blown into the atmosphere as hot exhaust.                                This is a big project to overcome. I don't think the EPA even knows how many chimneys there are across the country connected to larger natural gas appliances. Increasing Energy Efficiency is something that can benefit every company and building owner in reduced utility bills and the environment in reduced GHG emissions. Applying the technology of Condensing Flue Gas Heat Recovery will (1) Reduce Global Warming (2) Reduce CO2 Emissions  (3) Help to Conserve Water.   

 How much interest can be generated at convincing the public to Increase Their Natural Gas Energy Efficiency will also determine how many tons of CO2 will Not be put into the atmosphere, and how much water can be created.

What are other key benefits?

The US Department of Energy states that for every 1 million Btu's of heat energy that is recovered from the exhaust of combusted natural gas and this recovered heat energy is utilized, 117 lbs of CO2 will Not be put into the atmosphere. When this waste heat energy is recovered and utilized, instead of hot exhaust, cool exhaust is being vented into the atmosphere. The cooler the exhaust temperature is reduced, the greater the amount of water that will be produced                                                                                                  What natural gas is not wasted today, will be there to be used another day

A lot of natural gas utility companies across North America have custom incentive programs available where depending on the increase of efficiency that can be achieved will result in the natural gas client being reimbursed a percentage of the total projects installed costs. Each utilities energy program is unique but incentives can be anywhere from 10% to 50%.

What are the proposal’s costs?

There are no negative side effects to applying Increased Energy Efficiency measures. Installing custom engineered equipment like a Sidel SRU Condensing Economizer cannot be given a standard cost. There are too many variables when it comes to finding or creating the best application for applying the recovered heat energy.    At a number of previous installations labor to install was valued somewhere between 25 to 50 % of the equipment's cost.                                                            The Sidel SRU 100 is sized for a natural gas appliance of approximately 42,000,000 Btu's. With this equipment it is possible to increase the appliances energy efficiency from 70 or 80% to well over 90%.  Doing so could reduce the exiting flue gas temperature to less than 70 F. This could be reducing the facilities CO2 emissions by hundreds of lbs/hr and creating hundreds of gallons of distilled water.

The Sidel SRU Flue Gas Condenser has no moving parts to wear out. It requires little or no electricity to operate. It requires little or no maintenance. It is self cleaning on the flue gas side.

Time line

Sidel Systems has been selling the SRU Flue Gas Condenser for over 30 years. Most of these units are still in operation daily. With CO2 emissions now over the 400 ppm number there is a hope that businesses and industry will have a greater desire to want to take care of our environment, to want to reduce global warming and CO2 emissions and conserve water. Not only can they help benefit the environment, but it also will be profitable for their company.

With a Cap and Trade put into place at $30 or more dollars per ton of CO2 emitted for all natural gas consumers, we believe that this would create one of the biggest single methods of reducing the effects Climate Change.

Natural gas in 2016 is lower in cost than it was in 2000. Now that America is starting to sell LNG to other countries, cost of this commodity may increase. This would also help to show a shorter ROI, generating increased interest and sales.

Increased energy efficiency and reduced emissions and water conservation is starting to being realized around the world. Sidel Systems will follow these markets as they appear, helping these building owners and industries to do their part at taking care of the worlds environment.

Related proposals

This proposal could also possibly fit under the Industrial heading.

It's all about Increasing Energy Efficiency = (1) Reducing Global Warming  (2) Reducing CO2 Emissions  (3) Conserving Water