PSA System for Biogas Upgradation

Pressure swing adsoprtion, also known as PSA, is emerging as the most popular biogas upgradation technology in many parts of the world. A typical PSA system is composed of four vessels in series that are filled with adsorbent media which is capable of removing water vapor, CO2, N2 and O2 from the biogas stream.

During operation, each adsorber operates in an alternating cycle of adsorption, regeneration and pressure buildup. Dry biogas enters the system through the bottom of one of the adsorbers during the first phase of the process. When passing through the vessel, CO2, N2 and O2 are adsorbed onto the surface of the media. The gas leaving the top of the adsorber vessel contains more than 97% CH4

Biogas upgradation through PSA takes place over 4 phases: pressure build-up, adsorption, depressurization and regeneration. The pressure buildup is achieved by equilibrating pressure with a vessel that is at depressurization stage. Final pressure build up occurs by injecting raw biogas. During adsorption, CO2 and/or N2 and/or O2 are adsorbed by the media and the gas exits as CH4.

Depressurization is performed by equalizing with a second pressurizing vessel, and regeneration is achieved at atmospheric pressure, leaving a gas that contains high concentrations of CH4 to be re-circulated. During the regeneration phase, the bed must be regenerated by desorbing (or purging) the adsorbed gases. Purging is accomplished by reducing the pressure in the bed and back-flushing it with some of the concentrated gas product. The gas pressure released from one vessel is used by the other, thus reducing energy consumption and compressor capital costs.

Special adsorption materials are used as a molecular sieve, preferentially adsorbing the target gas species at high pressure. The adsorbent media is usually zeolites (crystalline polymers), carbon molecular sieves or activated carbon. Aside from their ability to discriminate between different gases, adsorbents for PSA-systems are usually very porous materials chosen because of their large surface areas.

Renewable Energy Trends in Germany

Germany has been called “the world’s first major renewable energy economy” as the country is one of the world’s most prolific users of renewable energy for power, heating, and transport. Germany has rapidly expanded the use of clean energy which now contributes almost one-fourth to the national energy mix. Renewable energy contribute as much as one-fourth of the primary energy mix and the country has set a goal to producing 35 percent of electricity from renewable sources by 2020 and 100 percent by 2050.

Solar Energy

Germany is the world’s biggest solar market and largest PV installer with a solar PV capacity of more than 32.3 GW in December 2012. The German new solar PV installations increased by about 7.6 GW in 2012, with a record 1.3 million PV systems installed across the country. Germany has nearly as much installed solar power generation capacity as the rest of the world combined and gets about 5 percent of its overall annual electricity needs from solar power alone.

Wind Energy

Germany’s wind energy industry is one of the world’s largest, and it is at the forefront of technological development.  Over half of all wind turbines in Germany are owned by local residents, farmers and local authorities which have tremendously improved the acceptance of wind turbines among local communities as they directly profit.

Being Europe’s primary wind energy market, Germany represents around 30 percent of total installed capacity in Europe and 12 percent of global installed capacity. Total wind energy capacity in Germany was 31.32 GW at the end of year 2012. Currently Germany is ranked third worldwide in installed total wind capacity with its share of total domestic electricity production forecasted to reach 25 percent by 2025.

Biomass Energy

Biomass energy is making a significant contribution to renewable energy supply in Germany and accounts for about 5.5 percent of the total electricity production in the country. Germany is the market leader in biogas technology and is also Europe’s biggest biogas producer. Last year around 7,600 systems with a cumulative capacity of 3,200 MW generated 21.9 billion kWh in the country, thus consolidating Germany’s status as a pioneer in clean energy technologies.

Renewable Energy Investment

Germany’s plan to phase out all 17 of its nuclear power plants and shift to renewable energy by 2022 is the largest infrastructure investment program in Europe since World War II. The country’s transition from nuclear energy-based power network to renewable energy systems will require investments of much as $55 billion by 2030.

Germany is the world’s third largest market for renewable energy investment which totalled $31billion in 2011. Sixty-five percent of investment in Germany was directed toward solar, with 29 percent ($8.5 billion) directed to wind. In addition, 700 MW of biomass capacity was added in 2011

The country offers generous feed-in-tariffs for investors across all renewable energy segments which is attracting huge private capital in cleantech investments. In 2010, the majority ($29 billion) of cleantech investment came from corporate investors across all sectors of the economy, including farmers, energy utilities, and industrial and commercial enterprises.

In the first six months of 2012, the amount of electricity produced from renewable resource rose from 20% to 25%, bringing Germany closer to its targets of 35% by 2020 and 80% by 2050. According to figures released by the government agency Germany Trade and Invest, 38% of the electricity produced by renewable energy during that period was through wind power, and almost 16% from solar.

Clean Cookstoves: An Urgent Necessity

Globally, three billion people in the developing nations are solely dependent on burning firewood, crop residues, animal manure etc for preparing their daily meals on open fires, mud or clay stoves or simply on three rocks strategically placed to balance a cooking vessel.  The temperature of these fires are lower and produce inefficient burning that results in black carbon and other short-lived but high impact pollutants.

These short-lived pollutants not only affect the persons in the immediate area but also contribute much harmful gases more potent than carbon dioxide and methane. For the people in the immediate area, their health is severely hampered as this indoor or domestic air pollution results in significantly higher risks of pneumonia and chronic bronchitis.

To remedy the indoor air pollution (IAP) and health-related issues as well as the environmental pollution in the developing world, clean cookstoves are the way to advance. But to empower rural users to embrace the advanced cookstoves, and achieve sustainable success requires a level of socio-cultural and economic awareness that is related directly to this marginalized group. The solution needs to be appropriate for the style of cooking of the group which means one stove model will not suit or meet the needs and requirements of all developing nation people groups.

Clean cookstoves can significantly reduce health problems caused by indoor air pollution in rural areas

Consideration for such issues as stove top and front loading stove cooking, single pot and double pot cooking, size of the typical cooking vessel and the style of cooking are all pieces of information needed to complete the picture.  Historically, natural draft systems were devised to aid the combustion or burning of the fuels, however, forced draft stoves tend to burn cleaner with better health and environmental benefits. Regardless of cookstove design, the components need to be either made locally or at least available locally so that the long term life of the stove is maintainable and so sustainable.

Now, if the cookstove unit can by powered by  simple solar or biomass system, this will change the whole nature of the life style and domestic duties of the chief cook and the young siblings who are typically charged with collecting the natural firewood to meet the cooking requirement.

Therefore the cookstoves need to be designed and adapted for the people group and their traditional cooking habits, and not in the reverse order. To assess the overall performance of the green cooking stoves requires simple but effective measures of the air quality. The two elements that need to be measured are the black carbon emissions and the temperature of the cooking device.  This can be achieved by miniature aerosol samplers and temperature sensors. The data collected needs to be transmitted in real-time via mobile phones for verification of performance rates.  This is to provide verifiable data in a cost effective monitoring process.

Biomass Energy Potential in Philippines

The Philippines has abundant supplies of biomass energy resources in the form of agricultural crop residues, forest residues, animal wastes, agro-industrial wastes, municipal solid wastes and aquatic biomass. The most common agricultural wastes are rice hull, bagasse, cane trash, coconut shell/husk and coconut coir. The use of crop residues as biofuels is increasing in the Philippines as fossil fuel prices continue to rise. Rice hull is perhaps the most important, underdeveloped biomass resource that could be fully utilized in a sustainable manner.

At present, biomass technologies utilized in the country vary from the use of bagasse as boiler fuel for cogeneration, rice/coconut husks dryers for crop drying, biomass gasifiers for mechanical and electrical applications, fuelwood and agricultural wastes for oven, kiln, furnace and cook-stoves for cooking and heating purposes. Biomass technologies represent the largest installations in the Philippines in comparison with the other renewable energy, energy efficiency and greenhouse gas abatement technologies.

Biomass energy plays a vital role in the nation’s energy supply. Nearly 30 percent of the energy for the 80 million people living in the Philippines comes from biomass, mainly used for household cooking by the rural poor. Biomass energy application accounts for around 15 percent of the primary energy use in the Philippines. The resources available in the Philippines can generate biomass projects with a potential capacity of more than 200 MW.

Almost 73 percent of this biomass use is traced to the cooking needs of the residential sector while industrial and commercial applications accounts for the rest. 92 percent of the biomass industrial use is traced to boiler fuel applications for power and steam generation followed by commercial applications like drying, ceramic processing and metal production. Commercial baking and cooking applications account for 1.3 percent of its use.

The EC-ASEAN COGEN Programme estimated that the volume of residues from rice, coconut, palm oil, sugar and wood industries is 16 million tons per year. Bagasse, coconut husks and shell can account for at least 12 percent of total national energy supply. The World Bank-Energy Sector Management Assistance Program estimated that residues from sugar, rice and coconut could produce 90 MW, 40 MW, and 20 MW, respectively.

The development of crop trash recovery systems, improvement of agro-forestry systems, introduction of latest energy conversion technologies and development of biomass supply chain can play a major role in biomass energy development in the Philippines. The Philippines is among the most vulnerable nations to climatic instability and experiences some of the largest crop losses due to unexpected climatic events. The country has strong self-interest in the advancement of clean energy technologies, and has the potential to become a role model for other developing nations on account of its broad portfolio of biomass energy resources and its potential to assist in rural development.

Share of Renewables in Energy Supply of UK

The Earth is facing a climate crisis, as the burning of fossil fuels to generate electricity and power our cars overloads the atmosphere with carbon dioxide, causing a dangerous atmospheric imbalance that’s raising global temperatures.

A report from the UN’s Intergovernmental Panel on Climate Change (IPCC) released earlier this month cautioned that the planet has just 12 years to dramatically curb greenhouse gas emissions, by overhauling our energy systems and economies and likely, our societies and political systems. Even a half degree rise beyond that would cause catastrophic sea level rises, droughts, heat, hunger, and poverty, spelling disaster for our species.

UK’s Commitment to Climate Change Mitigation

The UK government has committed to reducing carbon emissions by 80% of 1990 levels by 2050, a process that will involve overhauling our energy supply, which is responsible for 25% of greenhouse emissions in the country, just behind transport (26% of all emissions). But it may be too little too late. The government has already said it is reviewing these targets in light of the IPCC report and in the spring began consulting on a net-zero carbon emissions target for 2050.

But despite these dire prognoses and the enormity of the task facing us as a species, there’s reason to be optimistic. The UK has already managed to cut greenhouse gas emissions by 43% on 1990 levels, with much of the reduction coming from a 57% decline in emissions from energy generation. This is in part thanks to several providers offering you the chance to have a 100% renewable domestic energy supply.

Reduction in Coal Usage

The use of coal has plunged nearly overnight in the UK. In 2012, 42% of the UK’s electricity demand was met by coal. Just six years later, in the second quarter of 2018, that figure had fallen to just 1.6%. Emissions from coal-fired power stations fell from 129 million tonnes of CO2 to just 19 million tonnes over the same period.

A coal-free Britain is already on the horizon. In April 2017, the UK logged its first coal-free day since the Industrial Revolution; this past April we extended the run to 76 consecutive hours. In fact, in the second quarter of 2018, all the UK’s coal power stations were offline for a total of 812 hours, or 37% of the time. That’s more coal free hours than were recorded in 2016 and 2017 combined and in just three months.

When the UK does rely on coal power, it’s primarily to balance supplies and to meet demand overnight and during cold snaps, such as during the Beast from the East storm in March. The UK is so certain that coal is a technology of the past, that the government has plans to mothball all seven remaining coal-fired power stations by 2025.

Share of Renewables in Energy Supply

The decline in coal has been matched by an explosion in renewable energy, particularly in wind power. In the second quarter of 2018, renewables generated 31.7% of the UK’s electricity, up from under 9% in 2011. Of those, wind power produced 13.3% of all electricity (7.1% from onshore turbines farms and 6.2% from offshore wind farms), biomass energy contributed another 11% of the UK’s electricity, solar generated 6% and hydro power made up the rest of renewables’ pie share.

The UK’s total installed renewables capacity has exploded, hitting 42.2GW in the second quarter of 2018, up from under 10GW in 2010. That includes 13.7GW of onshore wind capacity and 7.8GW of offshore wind capacity—a figure which will get a boost with the opening in September of the world’s largest wind farm, the Walney Extension, off the coast of Cumbria, itself with a capacity of nearly 0.7GW. Solar panels contributed another 13GW of renewable capacity, and installed plant biomass infrastructure reaching 3.3GW.

However, while renewables are transforming electricity generation in the UK, our energy system consists of more than simply electricity. We also have to account for natural gas and the use of fuel in transport, and renewables have made fewer in roads in those sectors.

The UK is meeting just 9.3% of its total energy needs from renewable sources, short of the 15% it has earmarked for 2020 and far behind its peers in the EU, where Sweden is already running on 53.8% renewable energy.

Conclusion

Emissions are dropping overall in the UK, largely due to an ongoing revolution in electricity generation and a decisive move away from coal. But these reductions have concealed stagnant and even increasing levels of greenhouse gas emissions from other sectors, including transport and agriculture.

Our transition to a sustainable economy has begun but will require more than wind farms and the shuttering of coal-fired power stations. It must encompass electric vehicles, transformed industries, and ultimately changing attitudes toward energy and the environment and our responsibility toward it.

How the Biofuel Industry is Growing in the US

drop-in-biofuelsBiofuels were once forgotten in the United States, mainly when huge petroleum deposits kept fuel prices low.  With the increase in oil prices recently, the biofuel industry in the US is rising significantly.  Experts predict that this green energy efficient industry will continue to grow within the next 7 to 10 years.

The Source of Biofuels

Those who are concerned with the prospect of global warming love the potential use of biofuels. Produced either directly or indirectly from animal waste and plant materials, biofuels are less costly than other types of fuel.  Already in the national and global market, the trend for this fuel is rising.

Online Reverse Auction Software

Due to the growth of the biofuel industry, online software for energy brokers and energy suppliers is an available market for entrepreneurs.  The software to efficiently sell energy services to purchasers is a must have for suppliers and brokers.  The reverse auction process effectively conducts online business for those in the biofuel industry.

Both regulated and deregulated gas and electricity markets are involved in the reverse auction process in which the buyer and seller roles are reversed.  The buyer is given the option of testing and evaluating multiple pricing parameters to find a good fit.  Commercial, industrial, and manufacturing facilities take advantage of this platform.

Reverse Auction Benefits

Reverse auctions in the biofuel industry have been said to cut costs tremendously.  Although the seller pays a fee to the service provider, the bidding process cuts costs all around for both buyer and seller.  A situation in which both sides win is seen as a huge benefit by all involved.

As a very lucrative market, the biofuel industry benefits from reverse auctions.  Market efficiency is increased, and the process of obtaining the goods and services is enhanced.  Proper software and other technical aspects of the process is essential thus the reason that the online reverse auction software market is critical.  Quality and professional relationships are enhanced rather than compromised as is often the case in other markets.

Biofuel Market Projections and Uses

According to market research, the biofuel industry is expected to reach approximately 218 billion dollars by 2022.  A 4.5% growth is expected by 2022 as well.  Investors see these projections as an open door of opportunity.  By the year 2025, the increase is predicted to be at approximately 240 billion dollars.

Biofuel is used for other purposes besides first-generation fuel.  It is used in vegetable oil and cosmetics, and it is used to treat Vitamin A deficiency and other health issues. Biofuel is predicted to aid the improvement of economic conditions due to its health benefits and appeal to green energy supporters.  These factors explain the reasons for the projected growth and profit for this industry.

With the continued growth of the biofuel industry, reverse auctions will be a much-needed process.  The efficient software to accompany reverse auctions will keep the market flowing which will further aid the growth of the industry for years to come.

Overview of Bioenergy Technologies

A wide range of technologies are available for realizing the energy potential of biomass wastes, ranging from very simple systems for disposing of dry waste to more complex technologies capable of dealing with large amounts of industrial waste. Conversion routes for biomass wastes are generally thermo-chemical or bio-chemical, but may also include chemical and physical.

Thermal Technologies

The three principal methods of thermo-chemical conversion corresponding to each of these energy carriers are combustion in excess air, gasification in reduced air, and pyrolysis in the absence of air. Direct combustion is the best established and most commonly used technology for converting wastes to heat. During combustion, biomass is burnt in excess air to produce heat. The first stage of combustion involves the evolution of combustible vapours from wastes, which burn as flames. Steam is expanded through a conventional turbo-alternator to produce electricity. The residual material, in the form of charcoal, is burnt in a forced air supply to give more heat.

Co-firing or co-combustion of biomass wastes with coal and other fossil fuels can provide a short-term, low-risk, low-cost option for producing renewable energy while simultaneously reducing the use of fossil fuels. Co-firing involves utilizing existing power generating plants that are fired with fossil fuel (generally coal), and displacing a small proportion of the fossil fuel with renewable biomass fuels. Co-firing has the major advantage of avoiding the construction of new, dedicated, waste-to-energy power plant. An existing power station is modified to accept the waste resource and utilize it to produce a minor proportion of its electricity.

Gasification systems operate by heating biomass wastes in an environment where the solid waste breaks down to form a flammable gas. The gasification of biomass takes place in a restricted supply of air or oxygen at temperatures up to 1200–1300°C. The gas produced—synthesis gas, or syngas—can be cleaned, filtered, and then burned in a gas turbine in simple or combined-cycle mode, comparable to LFG or biogas produced from an anaerobic digester. The final fuel gas consists principally of carbon monoxide, hydrogen and methane with small amounts of higher hydrocarbons. This fuel gas may be burnt to generate heat; alternatively it may be processed and then used as fuel for gas-fired engines or gas turbines to drive generators. In smaller systems, the syngas can be fired in reciprocating engines, micro-turbines, Stirling engines, or fuel cells.

Pyrolysis is thermal decomposition occurring in the absence of oxygen. During the pyrolysis process, biomass waste is heated either in the absence of air (i.e. indirectly), or by the partial combustion of some of the waste in a restricted air or oxygen supply. This results in the thermal decomposition of the waste to form a combination of a solid char, gas, and liquid bio-oil, which can be used as a liquid fuel or upgraded and further processed to value-added products.

Biochemical Technologies

Biochemical processes, like anaerobic digestion, can also produce clean energy in the form of biogas which can be converted to power and heat using a gas engine. Anaerobic digestion is a series of chemical reactions during which organic material is decomposed through the metabolic pathways of naturally occurring microorganisms in an oxygen depleted environment. In addition, wastes can also yield liquid fuels, such as cellulosic ethanol and biodiesel, which can be used to replace petroleum-based fuels.

Anaerobic digestion is the natural biological process which stabilizes organic waste in the absence of air and transforms it into biogas and biofertilizer. Almost any organic material can be processed with anaerobic digestion. This includes biodegradable waste materials such as municipal solid waste, animal manure, poultry litter, food wastes, sewage and industrial wastes. An anaerobic digestion plant produces two outputs, biogas and digestate, both can be further processed or utilized to produce secondary outputs. Biogas can be used for producing electricity and heat, as a natural gas substitute and also a transportation fuel. Digestate can be further processed to produce liquor and a fibrous material. The fiber, which can be processed into compost, is a bulky material with low levels of nutrients and can be used as a soil conditioner or a low level fertilizer.

A variety of fuels can be produced from biomass wastes including liquid fuels, such as ethanol, methanol, biodiesel, Fischer-Tropsch diesel, and gaseous fuels, such as hydrogen and methane. The resource base for biofuel production is composed of a wide variety of forestry and agricultural resources, industrial processing residues, and municipal solid and urban wood residues. The largest potential feedstock for ethanol is lignocellulosic biomass wastes, which includes materials such as agricultural residues (corn stover, crop straws and bagasse), herbaceous crops (alfalfa, switchgrass), short rotation woody crops, forestry residues, waste paper and other wastes (municipal and industrial). The three major steps involved in cellulosic ethanol production are pretreatment, enzymatic hydrolysis, and fermentation. Biomass is pretreated to improve the accessibility of enzymes. After pretreatment, biomass undergoes enzymatic hydrolysis for conversion of polysaccharides into monomer sugars, such as glucose and xylose. Subsequently, sugars are fermented to ethanol by the use of different microorganisms. Bioethanol production from these feedstocks could be an attractive alternative for disposal of these residues. Importantly, lignocellulosic feedstocks do not interfere with food security.