The purpose of this report is to provide recommendations for climate change mitigation in the Canadian province of British Columbia (BC) in context to the Professional Engineers and Geologists of BC (APEGBC). This report aims to show how climate change is involved and integral in the activities undertaken by the professionals of APEGBC, how they can influence or choose to mitigate climate change in their professions, and the importance of doing so.
These are pictures taken in 2005 during a visit to one of the first LEED ‘Platinum’ building in India.
The solar panels on the roof are completely ineffective thanks to the lack of maintenance. There were probably never cleaned after the inauguration and the company received its LEED certificate.
In the basement, however, there were these three shiny diesel generators running at full throttle. New Delhi has often brownout and the company had to keep the air conditioning running.
Finally, we found the real source of energy – in the company gym.
The name of the company? British American Tobacco (BAT). Sustainable cigarettes for India!
Canada has the third largest natural gas production after USA and Russia . Total production according to Environment Canada, was about 202 GW in 2012.
A quick math: 202 Gw is 202*8670 =1,771,333 MWh per year and 1 GWh = 3,600 GJ, thus 202 GW = 6,377,000,000 GJ per year
According to NRCcan, burning natural gas produces is 56 kg of CO2 per GJ. Thus total emission of Canadian Natural Gas from combustion is 6,376,000,000 x 56 = 357,000,000,000 kgCO2eq/year or 357 Mt CO2Eq/yr. On top of that, Environment “Canada 2012 emission trends” estimates that GHG emission for Natural gas extraction only was 46 Mt/yr.
357 Mt combustion + 46 Mt extraction = about 400 Mt of CO2 eq. per year. Total CO2 for Canada is about 720 MtCO2/yr (2011). Thus ‘Natural’ gas generates the equivalent of more than half of total Canadian greenhouse gas emissions.
In addition, US EPA estimates that 3.2% of global gas production leaks into the atmosphere. (Well heads, valves, pipelines, etc,…- some other sources indicates 9% worldwide) For Canada, it would be the equivalent of 6.46 GW or 200,000,000 GJ leaked per year. The gas emitted is not CO2 but Methane (NH$) with a GHG factor 20 times more potent than CO2. Therefore, total GHG emission, including leakage, is: 357*(1-0.032+0.032*20) + 46 = 630 Mt CO2 eq !
Almost the entire Canadian inventoried emissions !
The bottom line: Natural Gas is definitely not green contrary to what industry and some governments want us to believe.
One may argue that a significant portion of the gas is exported to the US thus becoming US problem. But it does not make any difference as far as climate change is concerned.
On another note, Canada NG production is only 1/1,000,000 (one millionth) of total solar energy intercepted by earth. Would it be not smarter to develop solar energy rather than more shale gas?
Umicore voted #1 sustainability company by Corporate Knight Magazine. Interesting to see former Katanga’s Union Minière (in former Belgian Congo) switching to advanced metallurgy and getting their material from recycling rather than mining. Link between UMICORE and solar is by the production of advanced material for PV.
The company strategy focuses on four megatrends:
- Scarcity of resources
- Electrified transportation
- Clean energy production and storage
- Cleaner air.
Smart, forward thinking and an example for Canadian resources companies.
A recent study by NOAA (US National Oceanic and Atmospheric Administration) indicates a increase of atmospheric Methane, the likely result of oil and gas drilling boom.
The same NOAA has reported leakages rates at sites in Colorado and Utah at 4 and 9 % respectively. (Nature Journal)
Researchers at Cornel university have suggested leakage rates as high as 7.9%
It is an important issue because methane (CH4) has a Greenhouse gas potential 20 times higher than CO2. If the leakage rate is higher than 3.2% then coal will be a cleaner source!
Natural Gas may be less clean than claimed by industry and some governments. It would be worthwhile to analyze leakage rates in the new gas fields of northern BC, Canada.
Recently, I ordered from Vancouver, Canada, a new iPad mini together with a ‘iPad Mini Smart Cover” to Apple Online store. The electronic invoice included UPS shipping tracking. Then the iPad and its cover started their journey from …. China. You would imagine that Apple will have a warehouse full of iPad in Vancouver or somewhere in North America? Actually, the iPad is shipped from Shanghai by air and the cover from Shenzhen, 1,200 Km south of Shanghai. The 2 items will thus be air shipped individually.
The iPad arrived quite fast, in a couple of days but the cover took a week. Looking at the UPS tracking explains why.
The package was shipped from Shenzhen to Hong Kong, then from Hong Kong to Korea, then to Anchorage, Alaska, then to Louisville, Kentucky in the East (ignoring the fact that Vancouver, like Hong Kong and Anchorage is on the Pacific, and flying over Vancouver on its way to Eastern US see picture), then the package went North to Buffalo, NY, then to further North to Mount Hope, Canada , then turned West to Calgary, Alberta to finally find Vancouver Airport, back on the Pacific ocean. Finally, it went from the airport to a central UPS warehouse and from there to my home.
So, this precious little package traveled 17,587 km from the hands of a factory worker in China to clip on my iPad.
What a waste of energy to save on labour not mentioning the huge GHG content of this little item. The ‘smart’ cover is …well.. a cover, which comes is a plastic/cardboard package (another cover), itself wrapped in a plastic cover plus a foam protection cover and the whole is in shipping grade cardboard cover. Like a russian doll. (See picture).
The smart cover is designed to be as light as possible but the shipping package weights 300 gr. Applying typical shipping emission factors to the whole trip and the final package, I calculated a total CO2 equivalent emission (for transportation alone) of 2,888 grams or 10 x the weight of the package and about 30 x the weight of the cover itself. For comparison, cement manufacturers which are considered as some of the most GHG-intensive industry produces 1 tonne of CO2 per tonne of cement – thus a factor 1 . But the Apple ‘smart’ cover is a factor 30. Not so smart, after all. Neither eco-friendly, nor socially responsible.
It is much cleaner to produce electricity with natural gas turbines than in coal-fired power plant. This axiom supports the claim that switching from coal to gas is a solution climate change. Is it true? There must some scientific, quantitative method to verify this statement. Let’s do some (Grade 6) math….
If you yawn at number crunching and prefer to go directly to the conclusions, here are the key findings.
(1) The chemical reactions coal and gas are respectively:
- Coal: C + O2 → CO2 + heat (27 MJ/kg)
- Nat Gas: CH4 + 2 O2 → CO2 + 2 H2O + heat (43 MJ/kg)
(2) The atomic weight of the elements :
- Hydrogen: H : 1
- Carbon: C : 12
- Oxygen: O : 16
- CO2 : 12 + 32 = 44
- CH4 : 12 + 4 =16
(3) The ratio to CO2 are (table 1)
|Carbon C||C+O2 =>CO2||44/12= 3.67|
|Methane CH4||CH4 +2O2=>CO2+2H20||44/16= 2.75|
Table 1 means that
- Coal : the combustion of 1 kg of carbon produces 3.67 kg CO2.
- Nat gas : the combustion of 1 kg of nat gas produces 2.75 kg CO2.
Natural gas has a lower CO2 emission factor than carbon, thanks to the extra hydrogen molecules that produces water instead of CO2, giving also an additional combustion energy.
(4) The specific combustion heat values are:
|Natural Gas||1,000 (BTU/cf)||46.57||12.94|
GHG Emissions from fuel
(5) Assuming coal carbon concentration of 65% (in eia range *) and 100% of methane in gas, the above CO2 emission factors become:
- Coal: 3.67 * 0.65 = 2.38 kgCO2/kg coal
- Gas: 2.75 * 1 = 2.75 kgCO2/kg NatGas
( * Bituminous: Containing the widest range of carbon content (45% to 86%), bituminous is mainly used as a fuel to generate electricity, though some is used as coking coal to produce steel. The oldest and most abundant coal type found in the United States, bituminous coal makes up 45% of U.S. coal production by weight and 54% by energy intensity. West Virginia leads production, followed by Kentucky and Pennsylvania.- eia)
(6) Dividing (5) by (4) gives CO2 emission factor per unit of energy (heat value of the fuel)
The factors above are for the production of heat only from coal or gas. Extracting mechanical energy and then electrical energy from that heat implies additional energy losses.
First, there is a limit based on the laws of thermodynamics, known since the 19th century as the Carnot theorem, directly related to the difference of temperature between the steam/hotgas and the cooling system.
η = 1- Tc/Th (Tc: Absolute temperature of the cold side, Th: Abs. temp of the hot side (Fig 1)
For example, a typical steam engine using superheated steam at 300 Deg C and cooling water at 20 Deg C, has a maximum efficiency of:
ηmax = 1 – (273+20)/(273+300) = 48.8% i.e. regardless of any other parameter of the plant, f.ex equipment efficiency or steam boiler vs gas turbine, the efficiency of the system cannot exceed 48.8%. In other terms, half of the original energy in the combustible is lost in the cooling tower. (reason why co-gen is a good way to use this heat otherwise lost). Power plants rarely have max efficiency higher than 50%.)
Gas turbine can go higher. The best known efficiency for industrial gas turbine is 60% ( still 40% energy lost)
Other energy losses, thermal or mechanical, will add to the Carnot limit and the end , the efficiency of the power plant will be around 30% for coal and 40% for Natgas. It is calculated as follows:
GHG emission as function of electricity produced
(7) according to EIA: The heat rates for electricity, i.e. the amount of fuel heat value required to produce electric energy.: ( in BTU/kWh, 1,000 BTU = 0.293 kWh) are:
|Fuel||(a) BTU/kWh||(b) kWh(heat)/kWh(electric)||(c) Efficiency % = 1/(b)|
The table 4 means that:
- Coal: only 33% of the energy contained in coal is transformed into electricity and 67% is lost.
- NatGas: 42% of the energy contained in natural gas is transformed into electricity and 58% is lost.
(8) CO2 emitted per unit of electricity can be calculated by multiplying (6) by (7):
A (kgCO2/kWh heat ) x
B (kWh heat/kWh elec)
|t CO2/ MWH
|Coal||0.357 x 3.06||0.948||1|
|Natural Gas||0.213 x 0.508||0.508||0.5|
Table 5 indicates that the CO2 footprint of electricity produced by a gas-fired power plant is half the CO2 produced by a coal-fired power plant, representing a saving of 0.5 t per MWh.
That’s likely the basis for the claim that natural gas is clean. Although it still produces significant GHG emissions, bit less than coal?
But it that true? Not really…we still have to take into account fugitive emissions from natural gas.
GHG from Natural Gas Leakage
Natural gas leaks at various stage of its process: Well heads, pipelines, valves, flanges, connections, compressors, etc,… How much exactly? it still debated (and likely difficult to assess due to the nature of ‘fugitive emissions’). We have seen that natural gas is mostly methane, a GHG with a GreenHouse Warming Potential (GWP) 72 times greater than CO2 (IPCC GWP), i.e. the emission of one kg of CH4 is the same as the emission of 72 kg of CO2 equivalent.
As shown above, the difference of CO2 emissions between nat gas and coal is 500 kgCO2 per MWh electric. The GWP of 500 kg CO2 = 500/72 = GWP of 6.11 kg CH4. It means that if 6.11 kg of gas is lost before it reaches the power plant, there will be no difference in total emissions between a gas-fired or a coal-fired power plant. At what leakage rate will that threshold happen?
(8) It can be calculated as follow::
- Threshold of Methane leakage (500 kgCO2eq) 6.11 kgCH4
- Specific heat of nat gas:(4) 12.94 kWh (heat) / kg(nat gas) – See (4) above
- Heat rates: (7) 2.39 kWh(heat) / kWh(electricity) – See (7) above
- dividing (7) by (4) is 2.39/12.94= 0.185 kg(nat gas)/kWh electricity or 184.67 kg(natGas)/MWh.
- Leakage rate at the threshold is 6.11 / (184.67+6.11) = 3.21%.
EPA has estimated that this threshold equals 3.2 % . (EDF) confirming the above calculations.
Producing electricity with natural gas will not produce significantly less GHG per MWh than with coal (See Figure 2). If the leakage is greater than 3.2%, then gas is worst than coal.
On a more positive note, if a natural gas plant is replaced by renewable energy (hydro, solar or wind), the renewables will displace almost 0.84 t of CO2 per MWh produced. (assuming the US EPA estimated general leakage rate of 2.4%)
Natural gas is not a solution to climate change, solar is.
Here is a summary of a more in-depth number-crunching about respective impacts of electricity produced with natural gas versus coal. The detailed rationale is here.
The above graph summarizes the results. In the green zone, electricity produced by gas has less total GHG emissions than coal, in red, it is worst.
- The generation of 1 MWh of electricity by a coal-fired power plant produces about 1 t of CO
- The generation of 1 MWh of electricity by a gas-fired power plant produces about 0.5 t of CO2
- For that reason, gas-generated power is perceived as greener than coal-generated power.
- Gas leakage occurs during the extraction, processing and transportation of the gas.
- One tonne of Methane, the main component of natural gas, has the same climate change impact than 72 t of CO2.
- The leakage rate of natural gas is 2.4 %, according to US EPA.
- At 2.4% leakage rate, the total GHG impact of 1MWh produced with gas increases to 0.84 t of CO2.eq
- At a 3.2% leakage rate, the total CO2.eq produced by both coal and gas fired plant are equal.
- The perception that the electricity generated by gas is cleaner than electricity produced by coal is misguided.
- Generating electricity with renewable energy instead of a gas turbine will displace near to 0.84 t of CO2.eq per MWh produced. (if leakage is only 2.4%)
The new proposed Site C dam in BC, Canada is deemed to provide electricity to future LNG export plants in Kitimat and Prince Rupert.
What if that plan does not work and no extra power is needed? There is an alternative: EV (electric vehicle)
How much electricity does an EV consumes? Take a Nissan Leaf and get the fuel economy from US EPA
|Fuel economy||kWh/100 miles||34|
|Fule economy (Metric)||kWh/100 km||21.13|
|Miles per year||mi/a||15,000|
|Travel (Km) per year||km/a||24,140|
|Energy kWh per year||kWh/a||5,100|
|Cost of electricity per kWh||$/kWh||0.1|
|Annual fuel cost||$/yr||510|
Site C will produce 5,100 GWh/a electricity. Assuming average 5.7% lines and system loss – BC Hydro report 2012 page 94, Site C could supply the energy for 5,100*0.943/ 5,100 =943,000 EV per year = about half of passenger vehicles in BC.
It could have a lot of benefits of the economy and the environment.
For comparison, here is the energy requirement of an equivalent gasoline car – the Nissan Altima.
|Fuel Economy (Metric)||l /km||7.59|
|Distance travelled per year (Miles)||mi/a||15,000|
|Distance travelled per year (km)||km/a||24,140|
|Annual fuel consumption||l/a||1,832|
|Gasoline Price per litre||$/l||1.30|
|Annual fuel Cost||$/a||2,381.15|
|CO2 Emissions per Litre||CO2kg/l||2.29|
|Annual CO2 Emissions Million tonnes per year||CO2 MT/a||3.95|
|Fuel cost saving per year in billion $ per year||B$/a||1.7|
As the table shows
the benefits will be indeed numerous:
- 1/3 of BC cars become non-polluting, silent (and fun to drive).
- 1.7 Billion $ annual saving in imported gasoline replaced by made-in-BC electricity.
- For the same output, the BC economy costs less to run and has an higher local content.
- 4 million tonnes annual greenhouse gas reduction
- less VOC-emitting gas stations replaced by electric car charging station
- less gasoline trucks on the road.
- less refineries, less pollution.
- reduced demand from the oil sands.
- support to the development of dynamic local, cleantech industry instead of energy-intensive industries in China.
- and finally, a new market for other renewable power, for example solar-powered charging station.
We don’t have enough electric power and there may be a better use for Site C.