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Types of heat generation in Ukraine in 2016 and their cost

In 2016, private consumers of heat in Ukraine receive the heat from the following sources:

  1. The most common one is electricity, which means electric boilers, electric fireplaces and heaters of different kinds. Skipping some details, in most cases the ultimate source is hydropower. Possible sources are nuclear power and thermal power stations. For the most of final consumers, the distributing functions are performed by HCS (Housing and Communal Services companies) or companies of “Region-Town-Energo” type. At the beginning of 2016 the cost of “elektroheating” is about 1 UAH/kW.

To take into account getting the heat directly to the consumer’s apartment, house, or other compartment, to the cost of heat generation we will add amortized cost of the equipment, such as cost per hour based on the “25 years of the equipment running”. In this example we get 1 kW/h via ceramic heating plate 1200 UAH of cost. It serves at least 25 years, which means 25х365х24 = 219000 hours, or “amortized cost per hour” of 1200/219000 = 0,0054 UAH, i.e. it is inessential.

  1. This item probably should be the first, but I gave it up in favor of the previous one (that is why, perhaps, I write so subjectively). Anyway, the TEPLOKOMUNENERGO company offers heating for 1000 UAH for 50 sq. meters, regardless to the exact month of the heating season. To my apartment TEPLOKOMUNENERGO gave about 1 kW/h, or 1x24x30 = 720 kW/month, so I paid about 1,5 UAH/kW. For three months of the heating season, 1kW usually was not enough, for the remaining three months – too much… But that depends on the weather.
  2. Gas heating. It is 7,2 UAH/cbm, a cubic meter of gas produces about 10 kW, hence about 0,72 UAH/kW! It looks like gas even competes with electricity! Equipment in case of ordinary gas stove is immaterial. If you install a gas boiler and gas heating – well, let’s say the expenses will add another 10 percent – let it be 0,8 UAH/kW. The efficiency of a regular gas boiler is 85%, a condensing one – 95%, so, considering efficiency, the figures are the same as when heating by electricity. But, as in Ukraine a lot of consumers receive electricity at lower prices than 1 UAH/kW, plus “panic of recent years caused by political situation” – it is reported increasingly often of consumers giving up gas heating in favor of electricity or solid fuel.
  3. Elektroheating with heat pumps, with “30% of electricity consumption”. For example, if you install a heat pump for 100 square meters and spend 219 000 UAH on installation (it is easier to count that way), then ​​it is 0,2 UAH more for each 1kW just in amortized cost (I think you need 5 kW/h for every 100 sq. meters, so we divide 219,000 to 219,000 hours and to 5). But the cost per kilowatt is reduced to 0,3 UAH or 0,3 UAH + 0,2 UAH (amortized cost) = 0,5 UAH/kW. Obviously, the cheapest and most comfortable heating today is possible to arrange with heat pumps or expensive air conditioners (which is virtually the same thing).

Expansion of heat generation by heat pumps is limited because of the high cost of equipment.

  1. Solid fuel boilers or wood boilers. You need to burn 0.3 kg of wood to get 1 kW of heat. The average cost of timber today is 3000 UAH for 3000kg, or 1 UAH/kg.

0,3 UAH for 1 kW of heat – well, it’s competitive! The equipment costs are usually insignificant, if you do not strive for high efficiency and don’t try to invent some pyrolysis long burning boilers… But it is for a reason that I wrote about electricity (with or without heat pumps) as the most convenient, and therefore most expanding type of heating! Wood-burning boilers are not for lazy people, but for romantics, for people who are willing to throw wood into fire instead of fitness workouts. Or there can be a boiler station for large number of consumers, with a stoker – the idea is taking place when considering ecology, because the burning of wood and wood waste will not produce any harmful emissions.

  1. Heating with solar collectors. To solve at least 70% heating of 100 square meter by solar collector and get 5 kW/h in the sun you need to install a solar collecting system of 500 vacuum tubes 1800mm at 58mm. That’s $ 10000 worth of equipment, including heat accumulator (night and “non-solar” heat accumulation), and other related equipment. It is possible that in sunny weather, these 500 tubes will get 100% (let there be a better prognosis to facilitate failures). We have just 0,2 UAH/kW of amortized cost (219000 UAH for equipment divided by 219000 hours of operation and 5 kW). It seems like there are no more expenses – pumps for water or coolant pumping are insignificant (though in different schemes of taking heat from 500 pipes the cost may be essential). But you need to place these 500 tubes somewhere, as well as the heat accumulator, and there still is the most important thing – like in heat pumps – the start-up expenses! Also, the systems with solar concentrators may be regarded as solar heating systems – and they take even a few times larger area, than the 500 tubes, but are several times cheaper – you may found a lot of offers from different inventors on YouTube on installation of solar concentrators and heating thereof. Though solar heating is the cheapest and most advantageous, it is not expanding widely because of the initial cost and large area required for installing the equipment.
  2. Solar power generation, followed by the use of “photoelectricity” for heating. It is different from the preceding paragraph in the way of lower efficiency, but better convenience. http://msd.com.ua/solnechnaya-energetika/solnechnaya-energetika-v-ukraine-2015-2016-goda/ – here you can read more about this idea and the way of its realization. Let’s try and count the expenses through an example of a 10kW solar power plant, such as this one in the Kirovograd region., Video:

Averagely, such solar photovoltaic power plant gives 1200 kW per month of electricity, its cost with the installation is about $ 20000, or 500000 UAH, amortized cost of 1kW = 1,4 UAH.

In the case of feed-in tariff it is much more profitable to sell this 1kW “to the State” for 4 UAH, and get the heat for your house from other sources, so with the feed-in tariff the idea of ​​obtaining heat from solar electric power is meaningless.

Conclusion:

In today’s Ukraine the most profitable and convenient way to heat your premises is by electricity purchased “from the state”. Wood heating, if a consumer is willing to increase his “romantic time spending” is more profitable than electricity – but more troublesome. Gas heating remains convenient and profitable at the time – in this matter, as they say, every man to his own taste… If you already have gas heating, there is no point in giving it up, if you are facing a dilemma – you can think… Heat pumps and air conditioning also mean heating with electricity, but with three times less consumption, and, with the possible growth of the economy and the “wealth of consumers”, it is the most promising type of heating!

Yours faithfully,

Rashid

01/02/2016

www.msd.com.ua

Stay connected to your pets

 

 

Let us admit that pets are inevitable part of the family. However, in comparison with human members of the family we give them much less attention than they deserve. We usually see and interact with them in the morning and in the evening, and the rest of the time they are alone. Of course, when there are several pets in the family, they can interact with each other so they do not feel too lonely.

Caring owners always think how to entertain their pets while they are not at home. Some people hire dog walkers to exercise their dogs or ask neighboring kids to take care of their pets when they go to work. Others prefer to use professional services that look after pets, like kennels, pet boards or pet sitters.  But some owners have no possibility to take an advantage of such help because their pets do not like strangers or they are afraid of them. Some pets feel really uncomfortable close to other animals, so in kennels they feel stressed.

All that house animals need is love, attention and exercise. And you can give it to them even when you are not at home! Petcube is a perfect way to entertain yourself and your pet without efforts and you will definite receive maximum positive!

 

What is Petcube? It is an interactive pet monitor with help of which you will be able to communicate and play with your pet. Take pictures and record videos of your pets and do not forget to share them with your friends. Moreover, you can even share access to your Petcube to all your friends, family and anyone from Petcube network!

This camera also has a microphone and a speaker so you will be able to speak with your pet and he will hear your voice also. Hearing your voice will make your pet happy and thus your connection will become stronger.

And here is the most exciting part – Petcube camera has a laser in it and everybody knows how animals love to play with laser! You can exercise your dog or cat without being home! Bring into notice that you have nothing to worry about – this laser is absolutely safe for animals with no damage to their sight.

There are even more additional features that you might find really handy:

  • Sound alerts. You will get notification via your smartphone about any loud sound in your house.
  • Motion detection. You will know when your pet is active and willing to play. Especially useful for cat owners as cats like to sleep most of the day.
  • Auto play mode – create automatic laser movement routine so your pet can play with laser without your assistance.

MILLER EFFECT

While designing amplifiers, engineers may assume that the internal capacitances in the transistor are very small com­pared to the external capacitances. But in reality, capaci­tances do exist between the base and emitter (CBE) as well as between base and collector (CBC). This is shown in Fig. 4. It can be mathematically shown that the total input capacitance

CI = CBE + (1 + AV )(CBC)

In other words, the total input capacitance is the parallel combination of CBE and (1 + AV)CBC. The base-collector capac­itance has been amplified by a factor of 1 + AV. This is called the Miller effect.

As mentioned earlier, as the frequency increases, the value of the total input impedance decreases and thereby the fre-

Vc

MILLER EFFECT

Figure 4. Miller effect with the transistor internal capacitances CBC and Cbe.

MILLER EFFECT

Coupling Яс

MILLER EFFECT

MILLER EFFECT

VINO—— }|-

Cc

Emitter

by-pass

capacitor

Figure 5. The impedances of CC and CE are large at low frequencies, and portions of signal voltages may be lost.

quency response characteristics are affected. The Miller effect is especially pronounced with common-emitter amplifiers, be­cause they introduce a 180° phase shift between the input and the output. For example, the values of CBE and CBC may be small, say 5 pF and 4 pF. But when the transistor is used in an amplifier with a gain of 99, the total input capacitance will be large enough to affect the frequency output characteristics of the amplifier. This is because

ci — cbe + (1 + av )(cbc)

= 5 + (1 + 99)(4) — 405 pF

It is recalled that at low frequencies the coupling capacitor and the emitter bypass capacitors offer high impedances and therefore portions of signal voltage may be lost, as shown in

Fig. 5.

MILLER EFFECT

A’ 7

rj V feedback

^O, Miller — A1 — 1

The Miller effect is thus an extremely important concept in discussing feedback. Equations for calculating the Miller input impedance and Miller output impedance can be devel­oped, and are given below:

Vertical and Oblique Propagation

Before considering the behavior of a radio signal in a magne – toionic medium, we will state three theorems that relate oblique and vertical incidence propagation as depicted in Fig. 6. The first is the secant law, which relates the vertical-inci – dence frequency fv reflected at B to the oblique-incidence fre­quency fob reflected at the same true height. A typical deriva­tion of this relation is given in Ref. 5, and it is usually written as

JfL

2n m

■Bn& 2.80 x 1010Bn

fH —

(10)

and the angular gyrofrequency is given by le I

coH = — B0 ъ 1.76 X 10nB0

(11)

fob — fv sec ф0

(7)

Since electrons are much less massive than ions, the electron gyrofrequency affects the propagation of HF waves in the ionosphere more than the ion gyrofrequencies. For example, since B « 0.5 X 10-4 Wb/m2, the electron gyrofrequency is «1.40 MHz, which falls at the upper end of the medium wave band.

The Dispersion Relation. Using the recommended URSI (In­ternational Union at Radio Science) notation, the magne – toionic dispersion equation for a radio wave in a homoge­neous, partially absorbing ionized gas upon which a constant magnetic field is impressed is given by

The secant law, then, relates the two frequencies fv and fob reflected from the same true height (the distance BD in Fig. 6).

In order to determine sec ф and fob values from vertical – incidence soundings (which measure the virtual height h’), we need two more theorems. Breit and Tuve’s theorem states that the time taken to traverse the actual curved path TABCR in Fig. 6 at the group velocity vg equals the time nec­essary to travel over the straight-line path TER at the free-

E

Figure 6. Plane geometry describing vertical and oblique iono­spheric propagation.

n2 = 1 –

(1 – jZ) –

2(1 – X – jZ)

1/2

Y 4

IT

+ Yl2

±

4(1 – X – jZ)2

where

n = complex refractive index = (u _ jx) ш = angular frequency of the exploring wave (rad/s)

700

Sec ^(corrected)

3.0 2.0

16 20 24 28 32 36 40 44 48 52 56 60 70 80

Angle of departure (deg)

Figure 7. Logarithmic transmission curves for curved earth and ionosphere, parametric in distance between transmit­ter and receiver.

1.0

600

1=

is 500 ra

<d 400 sz

я

3 300 200 100 0

1

+ Yl2

=F I 7

2

(15)

wN = angular plasma frequency wH = angular gyrofrequency = B0|e|/m (rad/s) wL = longitudinal angular gyrofrequency = (B0|e|/m) cos в wT = transverse angular gyrofrequency = (B0|e|/m) sin в X = wN/w2 Y = wH/w Yl = wL/w YT = wT/w Z = v/w

в = angle between the wave-normal and the magnetic field inclination

The Polarization Relation. We begin by defining the polar­ization ratio R as

R = —Hy/Hx = Ex/Ey (13)

Then we can write the double-valued polarization equation as

In the upper F region of the ionosphere where the electron – ion collision frequency is very low, we may simplify the dis­persion and polarization equations by dropping the Z term (since v « 0). Equations (12) and (14) then become (for no absorption)

If we further simplify Eq. (12) by dropping the Y terms (no magnetic field), then we obtain n2 = 1 — X, which is equiva­lent to Eq. (1).

2 1 — X — jZ I 4 (1 — X — jZ)

2X (1 — X)

n2 = 1 —

n — 1

(14)

(16)

and

Y 4

YT

1/2-

X

2(1 — X) — YT2 ± [YT4 + 4YT2(1 — X)2]1/2

According to magnetoionic theory, a plane-polarized EM wave traveling in a medium like the terrestrial ionosphere will be split into two characteristic waves. The wave that most closely approximates the behavior of a signal propagating in this medium, without an imposed magnetic field, is called the ordinary wave, and the other is called the extraordinary wave. These terms are taken from the nomenclature for dou­ble refraction in optics, although the magnetoionic phenom­ena are more complicated than the optical ones. The ordinary wave is represented by the upper sign in the polarization Eq. (14), except when the wave-normal is exactly along the direc­tion of the magnetic field. Anomalous absorption occurs for the extraordinary wave when its frequency equals the elec­tron gyrofrequency (fH = |B| e/me « 0.8 to 1.6 MHz). These frequencies lie in the medium-frequency (MF) band; conse­quently the absorption of the extraordinary wave [A « (f — fH)2] is large and the polarization of the transmitted wave is important in the determination of the fraction of the incident power that goes into the extraordinary wave. This is espe­cially true near the dip equator, where the magnetic field is nearly horizontal and the field is usually vertical.

In addition to anomalous absorption effects near the elec­tron gyrofrequency, the wave may also experience significant lateral deviation. This is illustrated for vertical and oblique propagation in Sections 11.2.2 through 11.2.4 of Ref. 5.

If Eq. (16) is recast as a funtion of w and we define f(e) = j(sin2 e)/cos в and wc = (B0|e|/m) f(e), then it will be seen to describe an ellipse. The quantities f(e) and wc play an impor­tant part in the description of the polarization behavior of waves in magnetoionic theory. The magnitude of wc is inde­pendent of frequency, but varies with the angle between the wave normal and the magnetic field, в, whereas the sign of wc depends on the sign of the charge e and on the direction of the magnetic field. For longitudinal propagation wc = 0, and for transverse propagation wc ^ “.In the case where X = 1, the quantity wc primarily determines the polarization of the wave. A very complete discussion of R as a function of X and of the variation of the polarization ellipse is given in Ref. 21.

A more complete understanding of the behavior of EM waves in the terrestrial ionosphere may be obtained by em-

(23)

X

(24)

ploying two approximations. The quasilongitudinal (QL) ap­proximation applies when the wave is propagating nearly par­allel to the geomagnetic field, and the quasitransverse (QT) approximation applies when the wave propagates in a direc­tion nearly normal to the geomagnetic field. References 21 and 22 contain extended discussions of the QL and QT ap­proximations:

QT: YT4 » 4(1 – X)2Yl2

QL: YT4 << 4(1 – X)2Y2

The FBI has published a dossier on Steve Jobs

The FBI has published a dossier on Steve JobsThe FBI has published a dossier on Apple founder Steve Jobs, developed in the early 1990s, according to Agence France-Presse on Thursday, February 9. The document consists of 191 pages, was made public on the basis of the Law on Freedom of Information (Freedom of Information Act).

File was created in 1991 when the appointment was discussed Jobs in Export Council (The President's Export Council) under the U.S. President George HW Bush. Jobs at the time temporarily left the company Apple. The candidacy of Steve Jobs, in turn, has been approved, and he entered the presidential Export Council, U.S. Department of Commerce announced on February 9 after the publication of the dossier, reports Associated Press.