Before a biogas works is built or a biogas plan is implemented, a techno-economic appraisal should be made. For this, two sets of cost-benefit analyses have to be carried out:
The macro-economic analysis ( economic analysis ) which compares the costs of a biogas plan and the benefits for the state or the society.
The micro-economic analysis ( fiscal analysis ) which Judgess the profitableness of a biogas unit from the point of position of the user.
In judging the economic viability of biogas plans and units the aims of each decision-maker are of importance. Biogas plans ( macro-level ) and biogas units ( microlevel ) can function the undermentioned intents:
the production of energy at low cost ( chiefly micro-level ) ;
a harvest addition in agribusiness by the production of bio-fertilizer ( micro-level ) ;
the betterment of sanitation and hygiene ( micro and macro degree ) ;
the preservation of tree and wood militias and a decrease in dirt eroding ( chiefly macro-level ) ;
an betterment in the conditions of members of poorer degrees of the population ( chiefly macro-level ) ;
a economy in foreign exchange ( macro-level ) ;
proviso of accomplishments enhancement and employment for rural countries ( macro-level ) .
Cost OF A BIOGAS PLANT
Exact appraisals for the building and operation of biogas workss serve the undermentioned intents:
to compare the costs of alternate theoretical accounts ( optimum undertaking choice )
for the information of the users every bit far as future fiscal loads are concerned
the computation of funding demands including public subsidies ( budget planning )
Classs of Costss
Equally far as costs are concerned there are three major classs:
fabrication or acquisition costs ( production costs )
operation and care costs ( running costs )
The production costs include all disbursals and lost income which are necessary for the hard-on of the works e.g. : the land, excavation-work, building of the digester and gasholder, the piping system, the gas use system, the droppings storage system and other edifices. The building costs comprise rewards and stuff.
The production costs of biogas workss are determined by the undermentioned factors:
buying costs or chance costs for land which is needed for the biogas works and slurry storage ;
theoretical account of the biogas works ;
size and dimensioning of the biogas unit
sum and monetary values of stuff
labor input and rewards
The grade of engagement of the hereafter biogas user and his chance costs for labor.
To derive a unsmooth thought of the typical costs of a simple, unwarmed biogas works, the undermentioned figures can be used: entire cost for a biogas works, including all indispensable installings but non including land, is between GH?75-100 per M3 capacity. 35 – 40 % of the entire costs are for the digester.
The specific cost of gas production in community workss or big workss is by and large lower compared with little household workss. The cost for the gas distribution ( chiefly shrieking ) normally increases with the size of the works. For communal workss with several end-users of biogas, the piping costs are high and counterbalance the degression by ‘economics of size ‘ partially or entirely. In parts where works warming is necessary, large-scale workss would be more economical.
To maintain the building costs low, labor provided by the hereafter biogas users is desirable. Often, the whole digging work is done without hired labor. On the whole, a decrease of up to 15 % of the rewards can be effected by user-labour. If periods of low farm activities are chosen for the building of the biogas works, chance costs for labor can be kept low.
Table 8.1 Cost fractions of biogas works building
Cost fraction dome biogas works, %
Wagess for masonry
Wagess for gasholder building
Wagess for digging
Wagess for brick laying
Materials for gasholder
Materials for digester
The operation and care costs consist of pay and stuff cost for:
acquisition ( purchase, aggregation and transit ) of the substrate ;
H2O supply for cleaning the stable and blending the substrate ;
eating and operating of the works ;
supervising, care and fix of the works ;
storage and disposal of the slurry ;
gas distribution and use ;
The running costs of a biogas works with a professional direction are merely every bit of import as the building costs, for illustration for operation, care, disbursals for painting, service and fix.
Capital costs consist of salvation and involvement for the capital taken up to finance the building costs. For dynamic cost comparing the capital fixed in the works is converted into equal one-year sums.
The capital cost, apart from the depreciation rates or length of amortization, is dependent on the involvement rate at which the capital is provided. In each instance current involvement rates are to be laid down for the cost computation, which reflect the chance costs of the invested capital. To avoid deformations of the funding costs the comparings should ever be calculated with the same involvement rate.
Lifetime of Plants
In ciphering the depreciation, the economic life-span of workss can be taken as 15 -25 old ages, provided care and fix are carried out on a regular basis. Certain parts of the works have to be replaced after 8 – l0 old ages, e.g. a steel gas holder. The steel parts need to be repainted every twelvemonth or every 2nd twelvemonth. As a regulation, existent monetary values and involvement rates should be used in the computations. For cost computation rising prices rates are irrelevant as long as building costs refer to one point of clip. However, in ciphering the hard currency militias put aside for serving and mend the rising prices rate must be considered.
ECONOMIC EFFECTS OF BIOGAS PLANTS
When measuring biogas workss from a macro-economic point of position there are several grounds for monetary value accommodations in favor of the biogas engineering are required.
The production of biogas creates external economic systems. It means that the biogas production influences the public-service corporation map of the consumer ( i.e. better healthful and hygienic conditions ) and the societal public assistance map of the society ( i.e. reduced wellness costs ) . Sing national broad effects on energy balance, the biogas supply creates external economic systems on the balance of payments to the economic system ( import permutation of fossil fuels ) . As good external diseconomies so should be included, amounting to less income of import responsibilities because of permutation of traded fuel ( i.e. crude oil ) by biogas.
Biogas usage, replacing conventional fuels like kerosine or firewood, allows for the preservation of environment. It hence, increases its ain value by the value of i.e. forest saved or planted.
The monetary value of supplied energy produced by biogas competes with deformed monetary values on the national or regional degree of the energy market. Monopolistic patterns, which enable energy providers to sell their energy at a monetary value higher than the competition monetary value, still rule the energy market in many states. A decentralized, economically self-sufficing biogas unit hence, – under competitory conditions – provides its energy without market deformations.
Furthermore, other macro-economic benefits originate when comparing on the one manus the benefits of decentralized energy coevals ( improved power system security ) and the disadvantages of centralised energy coevals: incremental costs of investing in extra webs and the costs of losingss on the transmittal web, due to the distance of energy clients, may be added to the benefits of decentralized energy coevals from the macro-economic point of position.
Labour intensive decentralized biogas units, on the regional degree, better income distribution amongst income brackets and cut down regional disparities, heightening the attraction of rural life.
Investors should take at transporting out the building of biogas workss without any imported stuffs in the long tally. The lower the import content of the entire works costs ( i.e. sum of steel ) , the less the external diseconomies which may originate in effect of skiding exchange rates.
FINANCIAL VIABILITY OF BIOGAS PLANTS
Equally shortly as the cost and benefit constituents of a biogas works in planning can be quantified, and every bit shortly as other of import parametric quantities ( clip skyline, involvement rate, one-year allowances, exchange rates, rising prices rates ) are determined, the economic viability of a biogas works can be calculated.
Typically, the fiscal analysis of undertakings points out the fiscal viability of investing options.
Three types of inquiries need to be answered:
Which undertaking is the least expensive among an array of options that produce the same end product ( least cost analysis ) ?
Which undertaking shows the highest net benefit ( profit subtraction cost ) among an array of options ( cost benefit analysis ) ?
Is a undertaking a financially feasible solution to the job on manus? ( absolute viability,
i.e. the inquiry is dealt with whether the undertaking ‘s grosss are sufficiently high to run into capital cost and runing cost ) , and: Is a specific undertaking more economical than others? ( comparative viability ) .
The dynamic attack trades with a consideration of benefits and costs over several old ages
and therefore shall be pointed out more elaborate:
Investing standards are, as follows:
Net Present Value ( NPV )
The most common investing standard is the NPV and is defined as follows:
NPV – Net Present Value
Ct – Costss in twelvemonth T
Bt – Benefits in twelvemonth T
k – price reduction rate
t – figure of old ages from the present
n – entire figure of the old ages of the analysis period
Given a biogas works with an investing cost of GH?2000 within the first twelvemonth of the undertaking and presuming one-year running costs of GH?70 during the undermentioned 9 old ages of operation and gauging an one-year benefit of GH?450 during the operation clip ( due to incomes from gas production and fertiliser production ) , the NPV consequences as follows:
NPV = 2000/ ( 1.08 ) 0 + [ ( 450/ ( 1.08 ) 1 + 450/ ( 1.08 ) 2 + … + 450/ ( 1.08 ) 9 ) – ( 70/ ( 1.08 ) 1 + 70/ ( 1,08 ) 2
+ … + 70/ ( 1.08 ) 9 ) ] = GH?374
Using the net present value method the investing can number as being profitable as its NPV is positive. It means that the involvement rate on capital is higher than the false price reduction rate. Investing in the biogas works would let a higher return to the investor than an investing on capital market.
The methodological analysis described is suited for analyzing the comparative viability of a undertaking, i.e. it can state us whether one undertaking is more economical than another ( or others ) . It can hence be used for the analysis of the absolute viability of a undertaking. This measure answers the inquiry as to whether the return on investing for a undertaking is sufficiently high to cover its mean capital costs.
Internal Rate of Return ( IRR )
A farther standard which can be applied for the intent of viability computation is the internal rate of return ( IRR ) .
It is the price reduction rate at which the present value of cost is equal to the present value of the benefits. In other words, it is the price reduction rate at which the net present value is zero:
Where I = IRR
Assuming the undertaking informations of the illustration of NPV, the internal rate of return consequences as follows:
0 = 2000/ ( IRR ) 0 + [ ( 450/ ( IRR ) 1 + 450/ ( IRR ) 2 + … + 450/ ( IRR ) 9 ) – ( 70/ ( IRR ) 1 + 70/ ( IRR ) 2 + … + 70/ ( IRR ) 9 ) ]
The resulting involvement rate ( IRR ) at which the NPV is zero sums to 12.45 % . The investors determination to cover with a biogas works investing leads to high capital additions, since an IRR of 12.45 % exceeds the minimal acceptable rate of 8 % ( involvement rate ) .
The IRR method is closely linked with the NPV-method and is recommendable for viability computation for a individual undertaking, as the undertaking ‘s IRR is compared with the IRR of the market.
To the computation of the viability of a undertaking a complete digest of all input informations should happen carefully. The costs and grosss depend on the peculiar undertaking and proficient system and can, hence merely be accurately determined when all the parametric quantities of a specific application are known:
A important factor on the cost side is the size of the needed investing. The undermentioned elements make up the entire investing spendings:
planning and studies
works edifices and construction
conveyance ( including insurance )
imposts, responsibilities, revenue enhancements
The one-year benefits comprise the pecuniary flow from evaluable returns, nest eggs, etc. yielded by the investing. If the benefits arise in fiscal ( micro-economic ) footings or already include economic ( macro-economic ) benefits, this is due to definition of the chief ends which shall be achieved by an investing in a biogas works. Harmonizing to the chief aims of a biogas works, in fiscal footings the benefits may deduce from:
Power coevals: Naturally, merely the net energy addition can be counted, i.e. the procedure energy fraction ( for fomenters, pumps, warming, and any outside energy input ) must be subtracted from the sum gas output. If the generated power is sold, the returns are included in the computation. Any energy used to replace old outside energy inputs counts for nest eggs. One has to take into history a certain price reduction of energy monetary value if the generated power shall be sold because of linkage costs per end product ( due to little gas output of little workss ) .
Sludge: The permutation of digested sludge for chemical fertilisers can frequently give nest eggs in developing states, where in the past large sums of the stuff used as substrate had so far non been used as fertiliser. Accurate pecuniary rating is hard, because the fertilizing consequence of digested sludge is well influenced by the type of storage, the clime, the techniques employed in distributing out the sludge on the Fieldss and working it into the dirt, etc.
State the major classs in bing Biogas workss
Explain the factors that determine the production cost for biogas workss
What does the operation and care consist of?
Explain how the life-time of a works affect the costing
Give some economic effects of biogas workss
What pertinent inquiries need to be answered when carry oning fiscal analysis for biogas workss?
Calculate the NPV for a biogas works with an investing cost of GH?1000 within the first twelvemonth of the undertaking and presuming one-year running costs of GH?40 during the undermentioned 6 old ages of operation and gauging an one-year benefit of GH?300 during the operation clip ( due to incomes from gas production and fertiliser production.
Estimate the IRR for the undertaking in inquiry 7 above
State some of import cost informations required for fiscal analysis for biogas workss.
Explain two benefit informations required for fiscal analysis for biogas workss.