Volkswagen feels it is important to look beyond the benefits of driving a vehicle without tailpipe emissions and to take a holistic approach to e-mobility. The carbon offset program is a key element of Volkswagen’s holistic approach to e-Mobility. e-Golf customers can drive the vehicle confidently, knowing Volkswagen is addressing the vehicle’s environmental impacts through many stages of its lifecycle from production, distribution and charging.

—Joerg Sommer, vice president of product marketing, Volkswagen of America

This goes beyond just selling electric vehicles. It’s actually a corporate objective. We’re working toward this model of sustainable mobility—having CO₂-neutral mobility solutions. This really is what drives us. This is the whole Think.Blue perspective that we have. Our partnership with 3Degrees basically enables us to have a carbon-neutral car [the e-Golf] through manufacturing, distribution and the first three years of driving and charging.

—Stuart Gardner, Project Manager, Golf family, Volkswagen of America

Drive diversity in Volkswagen’s MQB platform, on which the Mk VII Golfs are based. Click to enlarge.

Trees are natural carbon sinks; they absorb carbon dioxide by photosynthesis, some of which is stored as carbon compounds in the wood—both during growth and even after harvesting, in the form of some wood products. In natural forests, when the trees die and fall, the process of decomposition by fungi, bacteria and insects results in the wood being reconverted to CO₂.

The ability of forests to function as net carbon sinks may be enhanced through carefully planned forest carbon sequestration projects, planning that will require accurate data on the carbon contained within tree species. Forest carbon sequestration, at a given spatial and temporal scale, occurs when the amount of carbon taken in and stored by the soil, trees (and resulting timber products) and other forest vegetation is greater than the total amount of carbon dioxide emitted due to respiration, decay, disturbances (such as harvests or fires) and emissions due to wood processing. In addition to the direct benefits of storing carbon, wood products have also been shown to have fewer associated greenhouse gas emissions compared with concrete or steel. These lower CO₂ emissions make a compelling argument for continued wood production and utilization.

—Jones and O’Hara (2012)

Foresters can improve the rate at which carbon is captured by increasing the growth rate of the forest, and optimizing the plant mix.

California’s redwoods are some of the most effective carbon-sequestering plants on the planet. Under the right conditions, redwood trees gain height and girth quickly. Underground, forest soils and root structures store even more carbon. Because redwoods live for thousands of years, they can be a very long-term source of carbon storage.

Garcia River Forest. The Garcia River Forest (GRF) is the first large working forest owned by a non-profit organization: The Conservation Fund (TCF). TCF acquired the 23,780-acre tract in 2004 for $18 million ($10 million California Coastal Conservancy, $3.5 million The Nature Conservancy, $2.5 million Packard loan, $2 million TCF).

The Nature Conservancy holds a conservation easement (8,321 acres) on the property and works in partnership with TCF to restore the most ecologically sensitive portions of the forest and the river.

GRF is located in the coastal mountain range of southwestern Mendocino County, California, and encompasses approximately one-third of the entire 72,000-acre Garcia River watershed. Large family and industrial timber interests (including the Garcia River Forest) own 75% of the watershed; 15% is under agricultural use, and 10% is held in small private ownerships. A 150-year history of forest harvesting has resulted in the current forest conditions.

The Garcia River Forest is dominated by redwood, Douglas fir and tanoak. Redwood forests house a number of threatened and vulnerable species, including the coastal tailed frog, endangered coho salmon and steelhead trout, as well as the northern spotted owl.

The property has been extensively harvested twice in the past. The primary forest component currently is pole-sized and small second-growth sawtimber (30 to 50 or more years old) occasionally in pure conifer stands, but primarily mixed in with hardwoods.

Garcia River and Forest. Click to enlarge.

These stands developed from the heavy harvests of the 1950 and 1960s, and have been since re-entered after 1988. In addition there are numerous hardwood-dominated stands, predominately 30 to 50 year-old tanoak. In general, the commercial quality timber stand is young, healthy, and vigorously growing. The forest is almost equally populated by redwood and Douglas-fir, with a small amount of sugar pine.

The timber stand is uniformly small, with an average merchantable tree size diameter of only 14 inches, and only 21% of the total sawtimber volume occurring in trees with diameters over 24 inches. Compared with historical composition and desired conditions, most stands are understocked with conifers and have a high degree of hardwood competition.

Garcia River Forest. Credit: Matt Gerhart. Click to enlarge.

In the original Resource Management Plan, TCF predicted that 341 animal species and 35 special status plant species occur on the property. The highly diverse vascular flora of the GRF is represented by at least 504 species in 277 genera and 78 families. Redwood habitat accounts for approximately 64% of the land-base. In most areas redwood would dominate if vegetation succession were allowed to proceed naturally.

The overall goal of TCF’s original forest management was to insure long-term and sustained-yield production of valuable forest products in a healthy, vigorous and diverse forest while also protecting and enhancing the associated values of watershed, wildlife, fish, soils, recreation and aesthetics.

Under TCF’s project management, there are two harvest management regimes—one for the reserve and one for the non-reserve portions of the property. The reserve area may be harvested but only for the explicit goal of speeding a given location’s return to late seral (i.e., climax) conditions. In most cases, this will mean little or no harvest in reserve areas.

The remaining portion is managed using an uneven-age selection silviculture regime. In some non-reserve areas of GRF, harvest prescriptions include a hardwood competition reduction treatment that is designed to reduce the prevalence of tanoak trees. This treatment is applied to stands that, at the time of the first scheduled harvest, had more than 50 ft₂ basal area of tanoak per acre.

This treatment, called “hack and squirt” by Scott Kelly, TCF’s Timberland Manager for all forest operations on the 74,000 acres of the North Coast Forest Conservation Initiative, involves punching a small hole into the forest, planting conifers, and killing the smaller tanoaks (<18") by cutting into the cambium and injecting Imazapyr, a non-selective herbicide used to control tanoak and Pacific madrone, as well as annual and perennial grass and broadleaved weeds, brush, and vines. Larger tanoaks as well as Pacific madrone are left for habitat.

According to Kelly, the Imazapyr treatment slowly kills the targeted trees, which eventually “kind of melt”, falling more gently onto the forest floor without disturbing the new conifers.

This process, and the use of Imazapyr, has in the past generated some controversy. However, in a case study of the Forest Stewardship Council’s (FSC) work and the Mendocino Redwood Company (MRC), Greenpeace noted that:

Areas that were clearcut by MRC’s predecessor now have excessive amounts of tanoak, a fast-sprouting species that competes with redwoods and Douglas fir, and is not commercially viable for MRC as a wood product. MRC, in order to restore the “original conifer balance” on the lands, manually applies Imazapyr, allowable under the FSC, in relatively small amounts (2ml per tree via syringe) to remove tanoak. The decision to use Imazapyr came after the company had first invested heavily to explore alternatives and ways to commercialise tanoak.

The use of this herbicide today has been the subject of criticism by local stakeholders, but MRC argues that other methods of removal of the tanoak, such as manual control with chain saws, could introduce greater amounts of chemicals in the ecosystem. MRC lists the amount of chemical usage on its website, monitors chemicals in the water table, doesn’t use the herbicide within the watercourse protection zones, and plans to phase out the use of the chemical by 2020. As a result of local concerns, certifying body SCS published a thorough discussion of the use of Imazapyr and found that MRC retained adequate levels of tanoak in areas treated with the chemical and that, for the most part, MRC’s use of the chemical did not present a non-conformance with relevant FSC indicators.

A “hack and squirt” clearing with new conifers. The yellow arrows point to some new redwoods; the red arrow points to a sprout of new redwoods from an old redwood trunk. Scott Kelly estimates that GCF now has about 100 acres worth of these little openings. Click to enlarge.

Management of the forest—i.e, helping the forest recover from its condition after 150 years of harvesting—requires much more than addressing silviculture or contracting out the selected logging of some areas.

In addition to already overseeing the logging of 3,134,590 board feet (785 log truck loads) of timber, the TCF team has decommissioned 16 miles of road to improve riparian conditions. Additionally, they have treated 644 road sites to reduce erosion and sediment delivery to the streams, helping to improve water quality and fish habitat.

Sediment savings from road projects are estimated to be 119,600 cubic yards—the equivalent of 12,000 dump trucks.

In addition, the team has placed 435 logs in rivers to improve coho and steelhead habitat, and regularly carries out owl surveys to track the Northern Spotted Owls living in the forest. (The fieldwork involved in an owl survey is a story in itself.)

TCF replaced a failing wooden bridge, which was adding sediment to the stream with this new steel structure. Engineers tore apart the old structure, excavated for new concrete retaining walls, and added rock armor to the slope. The new non-erosive structure cost about $400,000. Looking down to the water from the bridge, one can see fish flitting about in the clear water. Click to enlarge.

Carbon offsets. In February 2008, GRF became one of the first forests—and the largest—to receive verification as a source of greenhouse gas reductions under the protocols of the Climate Action Reserve, adopted by the California Air Resources Board in 2007.

Calculating stored carbon; “additionality”. To calculate how much carbon will be stored in an offset project such as Garcia River Forest, the managers factor in three projections. First is the carbon storage represented by the forest area if left unharvested. This is represented by the uppermost, green line above. Next is the baseline or business-as-usual carbon storage; i.e., the repeated logging of the forest with no other considerations that commercial. This is represented by the red line above. Finally is the management plan for the forest—i.e., how many trees the managers will remove either for sale or to better support the regrowth of the redwoods. (E.g., hack and squirt). This is represented above by the gold line. The delta between the carbon storage that would have been available under the business-as-usual plan and the TCF plan is the “additional” carbon storage provided by the project. The carbon storage that would have been provided by the trees TCF harvests, in other words, are not counted toward the long-term carbon accounting (typically done in 100-year chunks). Click to enlarge.

In the original project plan, TCF projected that after 100 years of growth, the Garcia River Forest (GRF) would store a total of 2,262,894.3 metric tonnes of carbon (8,304,822.08 metric tonnes of CO₂e).

After subtracting the baseline forest management scenario, the additional carbon stored in this forest as a result of The Conservation Fund’s (TCF) management would be approximately 1,135,118 metric tons (tonnes) of C (or 4,161,343 tonnes of CO₂). Applying a -10% uncertainty factor to this outcome, over 100 years (2004 to 2104) the GRF will have 3,745,208.7 tonnes of certifiable CO₂e offsets.

Modeled additional carbon stored in Garcia River Forest over time as a result of TCF management. The plan calls for 1,135,118 Mg of C (or 4,161,343 Mg of CO2) to be stored by 2014.Source: TCF Project worksheet summary. Click to enlarge.

e-Golf emissions. One of the Volkswagen Group’s ongoing objectives is the development of vehicles and components that, in their entirety, present better environmental properties than their predecessors. The Group documents the results of its efforts in the form of Environmental Commendations that consider the entire lifecycle of a vehicle from material production through to recycling.

All data in Volkswagen’s Environmental Commendation are checked and certified by the independent technical inspectorate TÜV NORD. The TÜV certificate confirms that the Life Cycle Assessment drawn up by Volkswagen is based on reliable data and that the method used to compile it complies with the requirements of ISO standards 14040 and 14044.

Volkswagen compared the e-Golf with the conventional reference models Golf Mk VII 1.2 TSI (gasoline) and Golf Mk VII 1.6 TDI (diesel), both in the basic versions with standard equipment. These models have comparable utilization characteristics and were offered on the European market in parallel to the e-Golf from the date of its market launch.

In addition, the Environmental Commendation also considers the impact of the source of the electricity used to power the e-Golf. For this purpose, a conventional power mix (EU-27) is compared with an eco-power product (“BluePower”) offered by Volkswagen’s cooperation partner LichtBlick. The main focus of the comparisons is on five environmental impact categories during production, use and recycling.

The “functional unit” for the Environmental Commendation assessment was defined as the transportation of passengers over a total distance of 150,000 kilometers (93,206 miles) in the New European Driving Cycle (NEDC).

The scope of the assessment was defined in so that all relevant processes and substances are considered and traced back to the furthest possible extent by modeling them at the level of elementary flows in accordance with ISO 14040.

For the lithium-ion batteries, Volkswagen developed an in-house model in cooperation with suppliers on the basis of the current state of the art as of 2012. Volkswagen assumed that the service life of the battery will correspond to that of the vehicle.

No environmental credits were awarded for the secondary raw material obtained from the recycling process; this corresponds to a worst case assumption, since in reality secondary raw material from vehicle recycling can generally be returned to the global production cycle.

Life Cycle Inventory data for the Golf VII 1.2 TSI (rounded values). Click to enlarge.		Life Cycle Inventory data for the Golf VII 1.6 TDI (rounded values). Click to enlarge.
Life Cycle Inventory data for the e-Golf (EU-27 power mix, rounded values). Click to enlarge.		Life Cycle Inventory data for the e-Golf (BluePower eco-power, rounded values). Click to enlarge.

A total of five environmental impact categories were identified as relevant and were then assessed in the study:

• eutrophication potential (EP)
• ozone depletion potential (ODP)
• photochemical ozone creation potential
• acidification potential
• global warming potential for a reference period of 100 years (GWP)

Broadly, and as would be expected, the values of the e-Golf for CO₂ and carbon monoxide (CO) are lower than those of the Golf models with conventional powertrains (gasoline and diesel), while the figures for sulphur dioxide (SO₂) and nitrogen oxides (NO_x) are higher. This increase is mainly a result of the manufacture and energy supply phase. If BluePower eco-power is used for charging the vehicle battery, there is a further reduction in emissions, but even so, at 47.1 kg (e-Golf, BluePower), SO₂ emissions are still above those of a conventional Golf VII 1.2 TSI, at 31.3 kg. This higher SO₂ value is the result of the lithium-ion batteries installed on the e-Golf.

For the full lifecycle, the e-Golf using the EU-27 power mix was assessed with 18.0 tonnes of CO₂, roughly half of which resulted from the manufacturing phase and an almost equivalent amount from electricity generation (fuel).

Under the BluePower scenario, the e-Golf was assessed with 9.3 tonnes of CO₂, predominantly from the manufacturing phase.

Comparative life cycle impacts of the Golf (gasoline and diesel) and the e-Golf, rounded values. Click to enlarge.

Partnering with 3Degrees. To help determine its carbon offset projects, Volkswagen teamed with 3Degrees, a renewable energy and carbon offset services provider. Volkswagen of America supports carbon reduction efforts in California and Texas, with projects geared towards forestry conservation and landfill gas capture.

The “purchase” of carbon offsets for the e-Golf in the US is not on a vehicle-by-vehicle basis. Volkswagen calculated an overall offset target based on US usage, the reduced use phase parameter (36,000 miles), projected sales and actual sales. This target then resulted in the investment in the carbon offset project.

In addition to the Garcia River Forest project, other Volkswagen-supported projects in the US include:

• Big River and Salmon Creek Forests. The Big River and Salmon Creek Forests, located in Mendocino County, Calif., were subject historically to land fragmentation and unsustainable logging practices. In an effort to protect the native redwood and Douglas fir forest, the land is now protected through a 16,000-acre land purchase, which was funded in part by the carbon offsets it offers to organizations like Volkswagen. Emissions reductions produced by the project are verified by an approved third party and registered with the Climate Action Reserve.

• McKinney Landfill. The McKinney Landfill project, based at a closed landfill in McKinney, Texas, works to capture gases that would otherwise be emitted into the atmosphere from anaerobic decomposition within the landfill. Benefits from the capture include odor reduction, improved water quality and future distributed renewable energy production. The sale of carbon offsets supports the gas collection and flaring project. The emission reductions are validated, verified and registered using the Climate Action Reserve’s Landfill Project Protocol. 


In addition to its own support for the McKinney Landfill project, Audi (another Volkswagen Group company) is also supporting (likewise teaming with 3Degrees), a UN REDD+ (Reducing Emissions from Deforestation and forest Degradation) project in Kenya to offset emissions from the A3 e-tron plug-in hybrid.

REDD focuses on protecting highly-threatened yet critical forest areas. It creates financial value for the carbon stored in forests by offering incentives for developing countries to reduce emissions from (converting) forested lands. REDD+ is a specific implementation of a climate change mitigation solution of the UN-REDD Programme. REDD+ goes beyond deforestation and forest degradation, and includes the role of conservation, sustainable management of forests and enhancement of forest carbon stocks.

Resources

• Garcia River Forest Integrated Resource Management Plan (August 2006)

• Project Summary Worksheet

• The e-Golf Environmental Commendation – Background Report

• Dryw A. Jones and Kevin L. O’Hara (2012) “Carbon density in managed coast redwood stands: implications for forest carbon estimation” Forestry 85 (1): 99-110 doi: 10.1093/forestry/cpr063

• Standiford, Richard B.; Weller, Theodore J.; Piirto, Douglas D.; Stuart, John D, technical coordinators. (2012) “Proceedings of coast redwood forests in a changing California: A symposium for scientists and managers.” Gen. Tech. Rep. PSW-GTR-238. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture