\»¼

62 /3

 + !"#$%&'()
ῌ

Challenge of Akita model to promote geo-heatpump system
Trial of hybrid use with conventional energy
and cost reduction
Isao TAKASHIMA
Faculty of Engineering and Resource Science, Akita University

Abstract
Geo-heat pump system is environmentally friendly and high e$cient in air conditional and snow melting. However, use of this system is negligibly few in Japan becauseof the very high cost. Akita model is the low cost underground construction system byuse of civil engineering machine and traditional well drilling method. Hybrid use,
combination of such underground system and conventional energy source, is the new
type of geo-heatpump application.

+ ῌ !" CO, #$%&'()*+," ./0 123456 789:;<=>?@)AB CDE-51"FGHIJK)CLI1" 6 MNOPQ !RSTIU +32* 8VWE<=)XY-5ZF [6\]^6 _`_QBabc45defghi$jklmnMorita et al., +32/o 4pq45#rs)tuv Iwx,-6 yz{ |)}~,-51" nW6 ,**+oF W6  4L|,-51|1F JK;<=4ASTI,-  nWGC,***o WE6  )I<=D6 ,**+ 8ST  bcOῌ Cw |I 4¡dJK^¢£ ;A)¤151"FJK¥¦51" , 1F ¨$© ¯156 +§456 ¨$©

4ª«¬­,®¦"4)

° /m ±¬4,-"²³´`µ¶4·¸ῌ? µ¶|I¹º

| /0 ¼ ',**04

 6/»+TU()V?fLῌῌ 63      !  " #$ % #& '(  ,- )*+)*./01 234  5  6#$,-%#$ &7%&89: ;#$<#&= 6> ,-#&? @A%#$ !#$#"BCD#&
 EF01G#  HI J#K 01L# MNO$PQR%+"B#$S&'Q$T U()V  *W9K?#  HI 6+,XY-+TZ.#& /0+   1[+ 23 #7\#$A4]CD#&, 
 6^_`a W5 67,-#& Db#;Cc8+
9:def+T .ῌ/ m ;<g2=U(hi>?@A#'Q$T H)jk'Q lBCD EmnopcFX3G+T)VqH+ U()V+RD IrLJs+ 'K +4 L* W5   tMNOu vwxy - zPQRC {8X MNSCX# lA%T|#$D  6}~S#&'+4 mnE)V A4 : WE%#$#UE, Vv  WrLVmn  Xlmn`-%#$ Y)Z WE#&% [\]v

E^_E#$D%Ou WrLmnop)V

A

VI?6%&% ,/* mm &$`g IE ',4 )V B4 : abca I)Vop '. m4  +* Y `a I + m d-Ee<gfLvwxX# WrLop%g hi%Tj  T kltM# mnTQWdXoc8#&'-4 fLvwx)V C4 : p¡ '+4  ',4fLvwx#&% WE% K WEf ,¢%&Vv# WrL)
V#op%£ q9]¤i#QRk
8 op+Tmn <gEkxa¥¦#& + m d . m aopd / m KW

rL§Q# +* m ¨dop%r©#& ª /* mm ops?g
ITQ U «g)Vt£# .*mm ¬­gfT®¯ p¡°$uK  + S±T+X°$² 'v³4 %)V ,ῌ- wD%x´S#&D%yµT D¶+ ·z¸# 1
 + 5I {*W%¹º 8 HIDº»¼64

 ,    !"#$ ,**,%

 - 

!"#$%&' ()*+,-+./0 123456 78 ,9 ,**+ :0 ;<= ,**, : +, ;>&?@ABCDEFGH6 IJKLMNOP -  ,**- &'()*+ A : ,./,0$ B : . m 1,0$ C : ./,0$ D :  2/,0,**- : + ;<=&QRS' TRUV1WX56 NY&'/Z[ . m' \C-+.

+ m ]^_M`a

bcd +2* m' ef&ghijk

S' IJKLM&lgIJKLMmn+ o  pH6-+./&iqjkrstX5' S&u( 0 v<=uP 3 v -* > -* wx\' -* wyz' &u( 1 v<=uP 1 v ,/ > ,/ wx\' -/ wyz {|}UVX
56 8 - j CDEZ ~CH6 - ;  + ;SUV H6 w ' IJLMDX56 , \DE& .* Ej>Hr' S-+./p1j =5 w C<=0+ῌmin DE . <= ,./ kWC-+./& .* mm, `aX5{   + ¡12&0`a , ¢0¬6r0&' + \& ,.+ kW

3.+-* mm  , £¤r' ¥¦§>r¨©&{ + `aª«' + m& ,- W



UV&SUVkr­®j{0 ¯°¨=56,/ῌ-* ' DE&´5kr 1./ ~{ µ¶' 0C-+./± ²³DE&& ..2 kW & + ¡12&3¶{{' S ·¸ 5 +  + m ¬6r0 S j C-+./0&'& .. WCDE DE j¹H{» /0 ¼ D,**0E

u ;6-<·I(=¸k]¹º .  )*+!",-. m  ,**+ῌ,**, *ῌ,  . m ῌ2  0 

65: !"#$%&'( ,**-ῌ,**.

:0 +*    !" #$% &'() *+,-./  0 1
2345
 6.

789:;<=>?@ABC D,**+ῌ
,**, E=>FG D,**-ῌ,**. E

 . m HIJKG DLME  NO1 NO / "*P!

 QRS$ TI UV W X /   !"./0123, m 45Y;' QZI"[\] V^_`a"!" %bcd!ef ^_g$[ N * h$ ,**- UWi8j D, m E k[\] , m "I@ABC QZl m[$\ n +** mcm 

D6 /E

o8p;qf % g$[ 'r'!stuvd! /*=>F +ῌ, wx"y$ #}~[$ $a"[$VGf / -ῌ. z{FG?f] +"$|DEugster et al., +33, : % & +33.E m["$ 'a" . 

(\ N  )
*$+ D-* m E ,- ,

$ TI   TI .0¡ "!¢£¤¥8¦ [ /0 N-1 § 2¨34© f 3*&'()ª'53&'()«6! ¬­[$D78¢®¯;=>E f°±ῌ,&'()­[ u 9­y  ²r³p´µ¶: ¢£¤¥8¦ [Sf

Cº¼|66 ῌ    

!"#$%

  &' CO, ( )%*+,-./0  1 2 , 3 45 6 !7891 "#$ %&:'   ;  <( )*+=>? @,ABC-.B   BD /!"#$%!0EF1
E2
G234H5IJKL M N67;:=   89:> S ?UF1VJ*(WOP$;Q<RS=T +* ?@A-X#BY

Z "#$CD[\E]^\[

 ' G2=F_EGH`>BI a+b cJJK aLMKNb d : , OP adb

Qe RST1Sf U$ Vg

h@WXiOPῌ >Y0 1  =Z [   f )%*j.kK\]^_K\  `U aOPK\cJJK b S!"#$%
acJJK 2*῍ c 7;:= del JK  6cJfgm b VJ*( a,b n%-%d : hi oOPj% S,pU kl mq S nE 6o OPj%bp% r9^_K\]q F1s ^_F1  `U j%rt sIJKL Mtuv  ' f =u  ῌ vB

V.wx%*S yῌyzf  s  ῍w xfyCzs ῎  {&|s}{  ~^\[  =Z [  ,p>? 6/!"#$%

 kl|S}

a-b ~d : 22S YS   IJKL6 VJ*.S  %w m 

CO, (ῌ/!"Sde 1 H589

,Y<VIJKL - =Z aP 1 hi  o aPp  Xi!+V.{: <X#F1# r W 2 aP[  rX =Z 7;:= ,x/  aP  %%/ cJJKhi=Z 7;:= hi Y89<lS a 0b < w%[  )%*j.k\C-.S   1 I  @,A BC-<z<C- * A  0IJKL -*῏-/   

 OaPC f  ES ' f 4!+V. a3   1 fS 0 ¡m8O¡¢£? X#%  ¤  BIJKL9S VJ*(E @¢{¥ xf¦ zaZ!+V.~ .£¤  O¡#wW  nE [§¨S  O¡§[S©¥f[S 0¦ Y:qª «{§P¬¨©  O­[YªfS r  ®[ ¯°«¬  ^\[ hi=Z G2Y& ±P­%JdS o ®²¯ °±³ X²!³´\  hi  ' ´5Y f mµ ¶Sµ= cJJK <  mµ¶·lª-5S hi=Z <¸Q 6mµ·< ª-¸¹1 º »¹QY» /0 ¼ r,**0s

'%;q;1|3 ¹.p

 0     -*῍  67 !"# $%&'(/  )*+,-. %
/012340 56
78. 90:;< =  ;"; >?@8/;)A 1  !"#$% COP & ' ()*+,-. */ 012 ,34+,-. ,/ ῌ-// 05678&9:; COP <=> / ?
@ AB CD C,**/E %FE

B;<C DEF?GHI
3J8,-( KL M >?@N OPQ!-  "#$R 56
 S3$TUV WXYZ$#[3\:]  %^&;<3 %;09056%^ῌ_`#$. ab;<'93
$C(cd3eL 9f)g$h*iW(. +jk,-$( lmn.o/$p0q$X r0 ,**0s 1tD$
!-tN ῌu)n.2Xvw xyz{?
|3%8/;12. K)vw}4~)a## F?GH5 vw D601 S?p]X$CD7p8< 9XB*93%& :8 g S?8x/" 5z>cdz$$ ;1.)¡v¢ῌ£!-  %$=#$;< |3 =¤¥;q;1>¦ ?§¨@56'©< ¨@56ªA1B|3« r¬­®Cs  r+s¯°vDE |3« r±s²³´wDµ )¡¶µES·¸¹F xGºH

º»¼,

68

    !"#$%& '( )*+,-.,/0123456 78456 94:;<=>?@AB CDEF?@ABGHI  JKLM NMMOPQ>,R56ST,MUVWXYZI῍ῌ

Eugster, W.G. et al. [+33,\ [] P^ [+330\\ : _`abcdefbghijk/flb  Iemnopqrstj fbuvwxy +3 ,22ῌ,30.
Morita, K., Matsubayashi, O. and Kusunoki, K. (+32/) : Down-hole coaxial heat exchanger
using insulated inner pipe for maximum heat extraction. Geothermal Resources Council,Transactions, 3, Part +, ./ῌ/*.

z{|ῌ7 8ῌ}k ~ῌ  ῌE7 ῌ[,**+\ : fbb

 Ie qrst fbuvwxy ,0 .,*ῌ.,0.
O [,**0\ :  fb yqrst fY+ fb,M
 ,2 +*1ῌ+,..
[,**/\ :  fb yqrst fby¡¢£¤ 

fb,M ,1 ,0-ῌ,1,.
¥¦ §ῌ7 8ῌ0123 [,**,\ : ¨<©ªe«¬­klgbqrst ®¯°±²³´jWµe¶·¸¹j fb,M ,. -0/ῌ-1+