Posts Tagged ‘carbon footprint’

What is Steenbergs’ carbon footprint?

Friday, June 5th, 2015

We seek to offset our carbon footprint so it is pretty small.

For 2014, Steenbergs has purchased carbon offsets for 72 tonnes of carbon dioxide (i), up from 17 tonnes in 2013.  This has increased, because we are now retiring even more of the greenhouse gases from our business.  This is in addition to using solar energy for 45% of our electricity usage and recycling as much of our waste as possible.

In previous footprints, we included direct greenhouse gases from energy consumed and business travel, together with those from the transport of goods to and from Steenbergs (ii).  In effect, this is the climate change impact resulting from what we do.

We actually reduced this direct carbon footprint by 25% between 2013 and 2014, down from 17 to 13 tonnes of carbon dioxide in 2014.

However, in looking more closely at our products’ lifecycle from farm-to-landfill, we were excluding virtual carbon embedded within our packaging and ingredients.  So that’s the greenhouse gases arising from farming and the manufacture of glass jars, steel lids and tins, together with impacts resulting from the disposal or recycling of packaging by our customers.  But this embedded carbon (or traded carbon) should be brought into consideration, or an oil trader becomes very green when you ignore the oil (iii).

This would be fine if our suppliers offset their climate costs, but they don’t.

82% of the carbon footprint in Steenbergs’ products is indirect:

Breakdown of carbon impact from Steenbergs in 2014

Breakdown of carbon impact from Steenbergs in 2014

42 tonnes of carbon dioxide relates to packaging, compared to the 13 tonnes from our business.

As for farming, we had naively assumed that its carbon costs are analogous to the carbon captured in the plants themselves.  Mike Berners-Lee in How bad are bananas? gives zero as the carbon footprint of an apple plucked from a tree in your garden.

Initial research gives the impact may be 0.87 kg CO2 per kg of spices; this compares to 12kg and 19 kg CO2 per kg of beef and lamb.  Farming might add another 17 tonnes carbon dioxide (iv).  Because this relates to what we sell, we will need to dig deeper.

But using this, Steenbergs’ total footprint over the lifecycle of its products is 72 tonnes carbon dioxide every year, or 6 families’ worth of carbon.  This has been offset through ClimateCare, which neatly uses projects such as its LifeStraw project that combine Steenbergs’ concern for water with issues of climate change.

Putting this into context, spices and herbs contribute a tiny proportion of the carbon footprint of a meal.

For example, the spices in rogan josh are 0.1% of the total footprint versus 89% for the lamb, or 0.5% in tandoori chicken compared to 85% for the poultry.  The herbs in spaghetti bolognaise are less than 0.01% of its total carbon footprint.  And last month we calculated the carbon footprints of your cup of tea, coffee and hot chocolate.

Notes

(i)    For ease, carbon dioxide is lazily used for carbon dioxide equivalent, so it includes carbon dioxide, methane and nitrous oxide gases.

(ii)   Steenbergs direct carbon footprint includes: electricity, business travel, water supply and sewerage, trade waste and recycled waste.  Steenbergs indirect carbon footprint comprises: freight for raw materials and packaging into Steenbergs and distribution of packed goods to our trade and consumer customers.

(iii)  See: Roger Harrabin (2015) CO2 cuts claims challenged by experts, BBC News, 19 March 2015, http://www.bbc.co.uk/news/science-environment-31952888; or John Barrett , Glen Peters , Thomas Wiedmann , Kate Scott , Manfred Lenzen , Katy Roelich & Corinne Le Quéré (2013) Consumption-based GHG emission accounting: a UK case study, Climate Policy, 13:4, 451-470, DOI: 10.1080/14693062.2013.788858

(iv)   I am unclear whether these figures are for the lifecycle of spices and/or include carbon captured in the plants themselves.  47.5% of carbon is locked in plant material, equivalent to 1.7kg CO2 per kilo.  So I am confused…

What’s the carbon footprint of your cuppa?

Tuesday, May 19th, 2015

It depends is perhaps the best answer.

It depends on what you drink and also on how you treat changes in land use.

For tea, the carbon footprint is 87 g CO2 for a mug of Steenbergs black tea taken with milk.

This includes the carbon footprint of brewed tea is 48 g CO2 for black tea, plus also probably for white, green and herbal teas.  But to this, we need to add another 39 g CO2 for any milk added, if (as most Brits do) your tea is made with milk.

If you use teabags, an extra 4 g CO2 is added, or 5% to the carbon footprint.

This compares with 129 g CO2 for a coffee.  About 60% of this comes from the coffee itself and the remainder from the milk.  For milkier coffees like a cappuccino or latte, the carbon footprint is much larger at 222 g CO2 and 318 g CO2, because more milk is used.

Hot chocolate have the biggest footprint with its major cost again the milk.  If you include land use changes for the cocoa, this becomes even larger with the cost of the mix doubling to 43 g CO2 per mug from 21 g CO2.

Carbon in hot beverages

Carbon footprint of hot drinks

What does this tell us?

We can all reduce our carbon footprints by drinking less milk.  We can have lighter teas drunk without milk, and cut back on large lattes and hot chocolates. White and green teas, Darjeeling or China teas and herbal infusions are other tasty possibilities.

Then, drink loose leaf infusions rather than teabags as this extra packaging ups your CO2.

Notes

Carbon dioxide is lazily used here to mean carbon dioxide equivalent, i.e. it includes carbon dioxide, methane and nitrous oxide gases.

These are comparable to figures in Mike Berners-Lee’s book “How bad are bananas?: tea with milk 71 g CO2, tea without milk 21 g CO2, milky coffee 71 g CO2, cappuccino 235 g CO2 and a large latte 340 g CO2.  His book did not have figures for hot chocolate, or at least I couldn’t find any.

How much water is needed for a mug of coffee or tea?

Wednesday, March 25th, 2015

The simple answer is not much – about 225ml.

But look deeper and we need to consider the rainwater needed to grow the coffee beans and tea leaves, plus the water used to process these and make any packaging.

Over the last few years, we have been looking at the environmental costs within Steenbergs products.  We have looked at our carbon footprint, possible pollution from cleaning chemicals and our recycling rates.

Our main finding has been that over the lifecycle of Steenbergs’ products the biggest environmental burden by far is the virtual water (i) to grow Steenbergs’ herbs, spices and teas and which is then transferred when these move from India or Sri Lanka to the UK.

In money terms, the environmental costs of water usage are 2½ times larger than our carbon footprint.  It’s about 138 million litres, roughly 55 Olympic swimming pools.

Furthermore, this virtual water dwarfs the actual water used to make a mug of coffee or tea – the 225ml we glibly used for our initial answer.

The virtual water in a mug of coffee or tea is 635 times and 151 times the actual water used to make your drink.

So 143 litres of virtual water are needed to grow your morning coffee, but only 0.2 litre of water is needed to make it.  In contrast, the virtual water for tea is 34 litres, one quarter of the water consumed in a coffee.

If you include the virtual water in milk, this bumps up the figures to a hefty 169 litres of water needed for a mug of coffee and 60 litres for a mug of tea.

For a hot chocolate, it’s even higher.  415 litres of water, mainly rainwater, are needed for each hot chocolate.  That’s a whopping 2048 times more water than your mug holds.

For cappuccinos and lattes, more coffee is used in making the espresso and quite a lot of milk is then added.  This ups the virtual water content to 340 litres for a cappuccino and 381 litres of your latte.

So next time you have a drink, pause for a moment to think about the massive amounts of rainwater that were needed for your small cuppa.

Graph that shows breakdown of water between blue and virtual water in hot beverages

Breakdown of total water in hot beverages

Notes:

(i) Virtual water is “the volume of water that is required to produce the product.”

(ii) Water footprint calculations:

water table

(iii) In our calculations, we have drawn heavily on the pioneering work of Chapagain and Hoekstra of the University of Twente (Netherlands):

Chapagain, A.K., Hoekstra, A.Y. (2004) Water footprints of nations, Volume 2: appendices, UNESCO-IHE Institute for Water Education, Research Report Series No. 16, November 2004

Chapagain, A.K., Hoekstra, A.Y. (2007) The water footprint of coffee and tea consumption in the Netherlands, Ecological Economics, 66: 109-118

Jefferies, D., Muñoz, I., Hodges, J., King, V. J., Aldaya, M., Ercin, A. E., Milà i Canals, L., Hoekstra, A. Y. (2012) Water footprint and life cycle assessment as approaches to asses potential impacts of products on water consumption.  Key learning points from pilot studies on tea and margarine, Journal of Cleaner Production, 33: 155-166